DOWNLOAD PDF BT Prime-Mover PMX/QMX Electric Low Lift Pallet Truck Service Manual_1996

SERVICE MANUAL Manual Part Number 302266-001 PMX/QMX ELECTRIC LOW LIFT PALLET TRUCK Effective Serial Number _MX0025268001

Read and observe all warnings on this unit before operating it.

DO NOT operate this equipment unless all factory installed guards and shields are properly secured in place.

ISSUED MARCH 1996

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PMX/QMX

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Table of Contents Section 0 Maintenance 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Truck Identification System Operation Specifications Maintenance and Adjustments Troubleshooting Component Removal and Installation Component Repair

0-2 0-3 0-4 0-14 0-21 0-21 0-21

Section 1 Transmission 1.1 1.2 1.3 1.4 1.5 1.6 1.7

Component Identification System Operation Specifications Maintenance and Adjustments Troubleshooting Component Removal and Installation Component Repair

1-2 1-6 1-6 1-6 1-7 1-7 1-12

Section 2 Electrical 2.1 2.2 2.3 2.4 2.5 2.6 2.7

Component Identification System Operation Specifications Maintenance and Adjustments Troubleshooting Component Removal and Installation Component Repair

2-3 2-22 2-37 2-38 2-45 2-82 2-88

Section 3 Hydraulic 3.1 3.2 3.3 3.4 3.5 3.6 3.7

Component Identification System Operation Specifications Maintenance and Adjustments Troubleshooting Component Removal and Installation Component Repair

3-2 3-8 3-8 3-8 3-9 3-11 3-13

Section 4 Frame 4.1 4.2 4.3 4.4 4.5 4.6 4.7

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Component Identification System Operation Specifications Maintenance and Adjustments Troubleshooting Component Removal and Installation Component Repair

4-2 4-10 4-10 4-10 4-11 4-11 4-11

I

Table of Contents

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MARCH 1996

IMPORTANT SAFETY REGULATIONS Warning symbols Always follow the warnings given in this Instruction Manual and on the truck to avoid accidents and incidents from occurring.

Warning levels Warning texts are given in four levels and provide information on the risks, describe the consequences and instruct how to avoid accidents.

DANGER Warns that an accident will occur if you do not follow the instructions.

The consequences are serious personal injury or possibly death and/or extremely large material damage.

WARNING Warns that accidents can occur if the instructions are not followed.

The consequences are serious personal injury or possibly death and/or large material damage.

CAUTION Warns that accidents can occur if the instructions are not followed.

The consequences are personal injury and/or material damage.

NOTE! Marks the risk of a crash/breakdown instructions are not followed.

if

the

Prohibitory symbols

NO SMOKING If smoking occurs in situations where a restriction against smoking is stated, a serious accident can occur.

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MARCH 1996

IMPORTANT SAFETY REGULATIONS

OPEN FLAMES PROHIBITED If open flames are used in situations where open flames are prohibited, a serious accident can occur.

GENERAL PROHIBITION If the prohibition is ignored, a serious accident can occur.

Ordinance symbols

SAFETY SHOES When the directive for safety shoes is given, safety shoes shall always be worn to avoid personal injury.

PROTECTIVE GLASSES When the directive for protective glasses is given, protective glasses shall always be worn to avoid personal injury.

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0.0 MAINTENANCE

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0.1

Maintenance 0.1 Truck Identification This repair manual covers the following BT Primemovers products: PMX and QMX Low Lift Pallet Trucks from serial number _MX0025268001 and above.

These trucks are manufactured by The Prime-Mover Company in Muscatine, Iowa, USA. The Prime-Mover Company reserves the right to change the information and specifications contained within this manual at any time without incurring any obligation relating to such changes.

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Maintenance 0.2 System Operation Federal and State laws require that operators be completely trained in the safe operation of lift trucks.

An Operator's Manual is attached to every BT Lifters lift truck when it is manufactured. If the Operator's Manual is missing from the truck a new manual may be obtained by contacting The PrimeMover Company, 3000 North US Highway 61, Muscatine, Iowa, 52761-5810, (319) 262-7700.

This manual is not a training manual. The information contained in this repair manual is intended as a guide to help the authorized technician safely repair the truck.

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0.3

Maintenance 0.3 Specifications I. Specifications A. Electrical - Maximum AMP Draw 1. Drive Motor Armature - Cable A2 12 volt a) In Top Variable Speed 1A 2. Lift Pump Motor - Cable A1 a) Against Pressure Relief

200A

24 volt 45A 115A

B. Hydraulic System 1. Type of Fluid

HYDO 32 (standard Texaco 15 (Freezer only)

2. Capacity

Approx. 1 quart

C. Tires and Wheels 1. Drive Tire

10.5 x 5 x 6.5 inches

2. Load Wheels

3.25 x 5 inches

F. Fluids and Lubricants 1. Hydraulic Fluid a) Standard b) Freezer application

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HYDO 32 Texaco 15

2. Lubricating Grease

Texas Refineries C & C #880

3. Transmission Oil

85W 90 API GL5

MARCH 1996

INCH (SAE) AND METRIC FASTENERS

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0.5

Maintenance INTRODUCTION Threaded fasteners like bolts, nuts, cap screws and studs are made to specifications that describe the mechanical strength and hardness of the fastener. A fastener used in a design application is selected according to its specifications. The Prime-Mover Company buys parts from many countries. There are several standards used by these countries in the manufacture of threaded fasteners. Many of these fasteners are similar, but cannot be used as direct replacement.

Service persons must use replacement fasteners that have the same specifications. Fasteners made to each specification have identification marks for that specification. This specification is commonly called “Grade” for SAE standards and “property” for metric standards. This section describes the identification of some common fasteners.

The metric system used by BT Prime-Mover is described as SI (International System of Units, also called SI in all languages). The SI system of measurement is described in ISO Standard 1000, 1973.

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Maintenance NOMENCLATURE, THREADS The thread design is specified by a series of numbers and letters for inch and metric fasteners. (See Figure 1). The diameter of the shank of the fastener is shown first in the series [M12=12mm, M20=20mm (1/2=1/2 inch, 3/4=3/4 inch)].

The number of threads per inch is normally not shown for inch nomenclature and only the UNC (Unified National Coarse) or UNF (Unified National Fine) is shown. This number of threads per inch is not shown because a UNC or UNF fastener has a standard number of threads per inch for a specific diameter.

The length of a shank is often indicated as part of the description of a fastener. This length is shown in inches for inch fasteners and in millimeters for metric fasteners.

A cap screw will have the following description: INCH

METRIC

1/2 x 13 UNC x 1-1/2 ABCD

M12 x 1.75 x 50 ABC

A = SHANK DIAMETER B = NUMBER OF THREADS PER UNIT OF LENGTH C = TYPE OF THREAD D = SHANK LENGTH

A = THREAD SIZE B = PITCH C = LENGTH

FIGURE # 1 THREAD DESIGN MARCH 1996

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Maintenance STRENGTH IDENTIFICATION The most common property classes for metric fasteners are 8.8 and 10.9. The property class is marked with a number on the head of the capacitor or on a nut. Property classes less then 8.8 are often not marked. Grades for inch bolts go from 2 to 8. Grade 2 fasteners normally do not have marks. The following tables show the marks that identify the grades and property classes for different fasteners.

When fasteners must be replaced, the new fasteners must be of the same strength or greater then the original fasteners.

The new fasteners must also be the correct NOTE: Identification marks are according to bolt strength. The higher the number or the increase in the number of marks indicates increased bolt strength.

TABLE # 1 Bolts and Screws Inch Fasteners.

Type of Strength Levels: SAE Grades Fasteners Markings Not Required

*

2

5

5.2

7

8

Hex Head Bolts & Cap Screws 5

Metric Fasteners.

Strength Levels: Property Classes

* Markings Not Required 4.6*

4.8*

5.8*

8.8

4.6

4.8

5.8

8.8

9.8

10.9

12.9

9.8

10.9

12.9

Markings for size M5 and Larger

8

Hex Head Flange Screws

Same As Above 5

8

12 Point Flange Screws

Hex Socket Head Markings Not Required Cap Screws 5.1

8.8

12.9

8.8

12.9

4.8*

9.8

4.8

9.8

SEMS

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MARCH 1996

Maintenance Strength Identification TABLE # 2 Studs and Nuts

Type of Fasteners

Inch Fasteners.

Metric Fasteners.

Strength Levels: SAE Grades

Strength Levels: Property Classes

*

* Markings Not Required

Markings Not Required

5.2*

5*

4.6*

4.8* 5.8*

8.8

4.6

4.8

8.8

9.8 9.8

8*

8.1

5.8

10.9 12.9 Markings for size 12.9 10.9 M5 and Larger

or

Studs

Optional Geometric Symbols for Size M5 through M11 ONLY.

2

Hex Nuts

Hex Slotted Nuts

Hex Flange Nuts

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5

8 or

or

5

8

9

5

8

9 9

5

8

10

12

10

12

10

12

Markings Not Required

5

8

9

10

12

5

8

9

10

12

5

8

9

10

12

5

8

9

10

12

Markings Not Required

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Maintenance Strength Identification TABLE # 3 Torque Nuts Type of Fasteners

Inch Fasteners.

Strength Levels: SAE Grades

A

Metric Fasteners.

Strength Levels: Property Classes

B

C

5

9

10

B

C

5

9

10

OR All Metal PreVailing-Torque Nuts

F

G 9

10

9

10

OR All Metal PreVailing-Torque Flange Nuts OR

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MARCH 1996

Maintenance Strength Identification TABLE # 4 Torque Nuts with Nylon Insert

Type of Fasteners

Inch Fasteners.

Metric Fasteners.

Strength Levels: SAE Grades

Strength Levels: Property Classes

5

9

10

5

9

10

OR Markings Not Required OR

Nylon Insert PreVailing-Torque Nuts

OR

Markings Not Required

9

10

9

10

OR

Nylon Insert PreVailing-Torque Flange Nuts

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Maintenance Conversion Table for Metric and English Units TABLE # 5 AREA Multiply

By

To Get

Multiply

By

To Get

inches²

6.452

centimeters² (cm²)

centimeters²

0.155

inches² (in²)

feet²

0.093

meters² (m²)

meters²

10.764

feet² (ft²)

LINEAR Multiply

By

To Get

Multiply

By

To Get

inches

25.4

millimeters(mm)

millimeter

0.039

inches (in)

feet

0.305

meters (m)

meter

3.281

feet (ft)

yards

0.914

meters (m)

meter

1.094

yards (yd)

miles

1.609

kilometers (km)

kilometer

0.621

miles (mi)

MASS Multiply

By

To Get

Multiply

By

To Get

ounces (oz)

28.35

grams (g)

grams

0.035

ounces (oz)

pounds (lb)

0.454

kilograms (kg)

kilograms

2.205

pounds (lb)

tons (2000 lb)

907.18

kilograms (kg)

kilograms

0.001

tons (2000 lb)

tons (2000 lb)

0.907

metric ton (t)

metric ton

1.102

tons (2000 lb)

POWER Multiply

By

To Get

Multiply

By

To Get

horsepower

0.746

kilowatts (kW)

kilowatts

1.34

horsepower(hp)

PRESSURE Multiply

By

To Get

Multiply

By

To Get

pounds/in²

6.895

kilopascal (kPa)

kilopascals

0.145

pounds/in² (psi)

pounds/in²

0.007

megapascal (MPa)

megapascals

145.04

pounds/in² (psi)

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MARCH 1996

Maintenance Conversion Table for Metric and English Units TEMPERATURE Multiply

By

To Get

Multiply

By

To Get

(°Fahrenheit-32)

0.56

° Celsius (C)

(°Celsius x 1.8)

+32

°Fahrenheit (F)

TORQUE Multiply

By

To Get

Multiply

By

To Get

pound inches

0.113

Newton meter (N.m)

Newton meter

8.851

pound inches (lbf in)

pound feet

1.356

Newton meter (N.m)

Newton meter

0.738

pound feet (lbf in)

VELOCITY Multiply

By

To Get

Multiply

By

To Get

miles/hour

1.609

kilometer/hour (km/h)

kilometer/hour

0.621

miles/hour (mph)

VOLUME Multiply

By

To Get

Multiply

By

To Get

inches³

16.387

centimeters³ (cm³)

centimeters³

0.061

inches³ (in³)

inches³

0.016

liters

liters

61.024

inches³ (in³)

quarts, U.S.

0.946

liters

liters

1.057

quarts, U.S (qt)

quarts, U.S.

0.83

quarts, Imp. (qt)

quarts, Imp.

1.205

quarts, U.S. (qt)

gallons, U.S.

3.785

liters

liters

0.264

gallons, U.S. (gal)

gallons, U.S.

0.83

gallons, Imp. (gal)

gallons, Imp.

1.205

gallons, U.S. (gal)

ounces

29.57

milliliters (ml)

milliliters

0.034

ounces (oz)

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Maintenance Conversion Table for Metric and English Units TABLE # 6 Property, Class

Property, Class

Property, Class

8.8*

10.9**

12.9***

Size and Pitch

M5 x 0.8 M6 x 1

N.m

lbf ft

N.m

lbf ft

N.m

lbf ft

5-6 8-10

lbf in.

44-53 71-88

7-8 12-14

lbf in 62-71 106-124

8-10 14-16

lbf in 71-88 124-142

177-221 lbf ft 30-33

30-35

lbf ft 22-26

34-40

lbf ft 26-30

60-65

44-48

70-75

52-55

115-130 180-210

85-96

M8 x 1.25

20-25

M10 x 1.5

40-45

M12 x 1.75

70-80 110-125

30-33

100-110

74-81

52-59

155-180

114-133

125-140

240-270

177-199

M20 x 2.5

170-190 340-380

251-280

450-500

M24 x 3

580-650

428-479

M30 x 3.5

1150-1300

M36 x 4

2000-2250

M14 x 2

M16 x 2

133-155

207-236

332-369

280-320 550-600

800-900

590-664

900-1050

664-774

848-959

1600-1800

1180-1328

1850-2100

1364-1549

1479-1660

2800-3150

2065-2323

3250-3700

2397-2729

406-443

* Property class 8.8, Protective Treatment CMHC Specification “H” (zinc phosphate), apply also to internally threaded fasteners made of property class 8 material. ** Property class 10.9, Protective Treatment CMHC Specification “H” (zinc phosphate), apply also to internally threaded fasteners made of property class 10 material. *** Property class 12.9, Protective Treatment CMHC Specification “H” (zinc phosphate), apply also to internally threaded fasteners of property class 12 material.

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MARCH 1996

Maintenance 0.4 Maintenance and Adjustments 0.4.1 Maintenance Planned Maintenance is a critical part of safe pallet truck operation. By following a regular schedule of planned maintenance procedures the correct and safe functioning of the pallet truck can be better assured. A good planned maintenance program will alert you to the need for adjustments and minor repairs and will greatly reduce the potential for unexpected failures.

An effective planned maintenance program will include a daily inspection to be made by the operator prior to each operating shift. This should include a visual inspection for damage, leaks, and fluid levels as well as testing for the correct operation of safety devices.

In addition to the operator's daily inspection a regular scheduled planned maintenance service should be performed by a qualified BT Lifters technician. This service should include a thorough visual inspection, lubrication of service points, operational checks and minor adjustments.

The basic planned maintenance visit should be made every 200 operating hours or once a month.

More detailed service should be performed once a year. A comprehensive schedule of planned maintenance operations and detailed planned maintenance procedures are in the sections that follow.

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0.15

Maintenance Planned Maintenance Schedule Services to be Performed Daily or at each 8 Hour Operating Shift Item

Service to be Performed

Notes

Battery

Charge and Check Water

Equalize Charge Once a Week

Hydraulic System

Inspect for Leaks

Frame/Sheet Metal

Inspect for Loose, Damaged, or Missing Parts

Wheels/Tires

Inspect for Damage and for Trash in Bearings

Functions/Operations

Test for Proper Operation of All Functions

All Shields must be in Place

Safety Devices must Function

Services to be Performed Every Three Months or Every 200 Operating Hours Item

Service to be Performed

Daily Inspection

Perform Daily Inspections

Transmission

Check Fluid Level

Brakes

Adjust as needed

Battery

Check Specific Gravity

Electrical Connections

Check for Tight and Clean

Contactor Tips

Inspect for Arcing and Pitting

Hydraulic Reservoir

Check Fluid Level

Frame Lube

Lubricate All Grease Fittings

Pivot Points

Lubricate All Pivot Points

Motor Brushes

Inspect for Minimum Length

Drive Motor

Blow Out Drive Motor Vents

Notes

Do Not File Tips

Drip Lube with 10 WT Machine Oil Compressed air used for cleaning must be reduced to less then 30PSI and then only with effective chip guarding and personal protective equipment

Service to be Preformed Every 2000 Operating Hours Item

Service to be Performed

Daily Inspection

Perform Daily Inspection

Monthly Inspection

Perform 200 Hour Inspection

Transmission

Drain, flush and Refill

Battery

Remove from truck and clean

Hydraulic System

Drain, Flush and refill

Hydraulic System

Set Pressure Relief Valve and Load Test

Brakes

Inspect Brake Shoe Wear

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Notes

Also Clean Battery Compartment

MARCH 1996

Maintenance Planned Maintenance Schedule Maintenance A. Hydraulic Oil Level B. Transmission Pivot Tube C. Handle Pivot D. Transmission Oil Level E. Transmission Oil Level F. Transmission Drain Plug G. Lift Linkage (lube package & freezer) H. Load Wheel (lube package & freezer)

A B C

D F

H G 0.4.3 Planned Maintenance Procedures This section describes how to perform the services listed in the Schedule of Planned Maintenance Operations. As with the “Schedule” this section is sub-divided into service intervals.

Services to be performed daily or at each 8 hour operating shift: The daily inspection is to be made by the operator prior to each operating shift. It is the operator's responsibility to report any defects to the proper authorities and the truck should not be operated until it has been inspected and repaired by a qualified technician. The operator is ultimately responsible for the safe operation of this pallet truck.

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0.17

Maintenance Battery The battery should be charged when it reaches the 80% discharged level. This is indicated on the optional Battery Discharge Indicator when the single red LED bar on the far left is illuminated. A warning will be given at the 70% discharged level by means of the two red LED bars flashing alternately on and off. If the truck is equipped with the optional Lift Interrupt then lift lockout will occur at the 80% discharged level. If the optional Battery Discharge Indicator is not mounted then the battery should be charged after 6 to 8 operating hours.

Hydraulic System Inspect the entire truck for leaks; especially around the hydraulic pump assembly and the lift cylinder.

Any sign of oil on the floor under the truck is an indication that the truck may be leaking hydraulic oil or transmission fluid. Report any problems to the proper authorities and do not operate the truck until it has been inspected and repaired by a qualified technician.

Frame/Sheet Metal Inspect the truck for loose, damaged or missing parts. All shields must be in place and functional.

Report any problems to the proper authorities and do not operate the truck until it has been inspected and repaired by a qualified technician.

Wheels/Tires Inspect wheels and tires for wear and damage.

Trash wrapped around wheels and axles will cause premature tire wear and bearing damage. Any trash should be removed before operating the truck and the floors should be kept clear of trash to prevent damage to the wheels and tires.

Functions/Operations Test the truck for the proper operation of all functions; including the travel controls, lift and lower functions, the brakes and the emergency reverser button. Safety devices must be operational. Report any problems to the proper authorities and do not operate the truck until it has been inspected and repaired by a qualified technician.

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MARCH 1996

Maintenance SERVICES TO BE PERFORMED MONTHLY OR EVERY 200 OPERATING HOURS: The monthly planned maintenance service should be performed by a qualified technician.

Daily Inspection All of the services and inspections listed above for the daily inspection should be performed at this time. The inspection procedure should be more thorough and minor deficiencies should be corrected.

Transmission Check the transmission fluid level. The level check point is a plug on the side cover of the transmission about 100 mm (4") above the bottom of the transmission case. Remove the plug and inspect the level of the fluid inside the transmission case.

The fluid level should come to about 10 mm (3/8”) below the plug and should never be above the level of the plug.

Brakes The brakes should stop a fully loaded truck at full speed in approximately one truck length and should hold the truck from rolling on a 10% incline. The brakes should fully release when the control handle is moved down 12° from the fully raised position and should reapply when 28° above the fully lowered position. Adjust the brake linkage as required.

Battery At the 200 hour or monthly service interval the specific gravity of the battery should be measured with a battery hydrometer. The difference in the highest cell and lowest cell readings should not be greater then 20 (.020) points.

An average battery will have a specific gravity of 1.170 at the 80% discharged level. However, there are many different batteries on the market and only the battery manufacturer can accurately determine the fully charged and 80% charged levels. Contact the battery manufacturer for this information.

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0.19

Maintenance Electrical Connections All electrical connections should be checked that they are clean and tight. Plug- in connectors should be unplugged and plugged back in to clean the terminals. If the truck is equipped with any of the cold-storage, freezer use, or corrosive environment application packages then the di-electric compound in the plug-in connectors should be renewed. This compound is available through the parts department of your authorized dealer.

Contactor Tips Inspect contactor tips for arcing, pitting, or burning.

Minor pitting of the tips is not a problem, however, if the tips are pitted through the tip to the copper bar the tips should be replaced. DO NOT file tips and replace tips only in complete sets. Some contactors have concealed tips or are fully sealed so that tips cannot be replaced.

Motor Brushes Inspect the drive and the pump motors for brush wear and condition of the commutator. Minimum brush lengths are given in the specifications section of this manual. As a rule of thumb the brushes should be replaced if the brush spring is within 1/16 of an inch of touching the brush holder.

Drive Motor Blow out the drive motor fan and vents. Check for any signs of oil on the drive motor fan and air vents.

Check for any damage to the fan or air vents.

Compressed air used for cleaning MUST be reduced to less than 30 p.s.i., and then only with effective chipguarding and personal protective equipment.

Hydraulic Reservoir Check the fluid level in the hydraulic reservoir. The level check point is the breather cap on the reservoir. Remove the breather cap and check the level of the hydraulic fluid by looking down inside the elbow that the breather cap screws into. The fluid level should come up to the bottom of the elbow when the pallet forks are fully lowered.

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MARCH 1996

Maintenance Frame Lube The pressure type grease fittings (zerk fittings) should be lubricated with Texas Refineries #880 Crown and Chassis lubricating grease. The total number of grease fittings depends on the truck options when built. A truck with a cold-storage, freezer use, or corrosive environment application package will have more grease fittings then a standard truck. Look for flush type grease fittings on the load wheel axles and wheel fork pins. Regular fittings may be found on the ends of the pull rods at the transmission mounting bearing, and the lift cylinder mounting shafts.

Pivot Points There are some pivot points and other items that need to be lubricated but do not have grease fittings. These include, but are not limited to, the control handle mounting shaft, the handle return chain, and the pull rod pins (on standard trucks).

Lubricate these non-greasable wear points with a drip oil can using 10 wt. machine oil.

SERVICES TO BE PERFORMED ANNUALLY OR EVERY 2000 OPERATING HOURS. The annual planned maintenance service will take a longer period of time to complete then does the monthly service. This would be a good time to arrange other repairs that have been noted on the monthly service.

Daily Inspection and Monthly Inspection All of the services and inspections listed above for the daily and monthly inspection should be performed at this time. The inspection procedure should be more thorough and minor deficiencies should be corrected.

Transmission The transmission fluid should be drained. The drain port is the lower left hand bolt holding the side cover in place. Remove the bolt to drain the transmission fluid. Flush the transmission case with safety solvent by pouring clean solution into the level check plug in the side cover and allowing it to run out of the drain port while the transmission is MARCH 1996

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0.21

Maintenance running with the drive tire off the ground. Stop the flushing when the solution is running clean. Allow the solvent to drain well before replacing the drain plug bolt. Replace the drain plug bolt. Refill the transmission with the proper oil before operating truck.

Battery At the 2000 hour, or annual service interval it is recommended that the battery be removed from the truck for cleaning. Use fresh water to wash the battery and a soft, non-conductive brush to scrub the battery. Soda may be used to neutralize acid on the outside of the battery but care must be taken so that soda and water does not enter the battery cells.

Also clean the battery compartment in the truck.

About every three years the battery should be inspected and serviced by the battery manufacturer's authorized service center.

Hydraulic System The hydraulic system should be drained, flushed and refilled, and the pressure relief valve setting should be checked and adjusted.

Disconnect and remove the hydraulic pump assembly. Remove hydraulic reservoir from assembly. Drain the oil and clean the inside of the reservoir. Drain oil from hydraulic hose and lift cylinder. Reassemble hydraulic pump assembly and re-install on truck. Fill reservoir with proper fluid.

Operate raise and lower function several times to purge air from system. Re-check fluid level. Put rated truck capacity load on forks and adjust pressure relief valve, if necessary so that truck will lift rated load.

Brakes Remove brake drum and inspect brake shoe linings and brake drum for wear. If the brake drum is damaged or worn a new drum should be fitted. The brake shoes should be replaced if the linings have worn down so much that the brakes will not meet stopping and holding specifications. See the procedures for adjusting brakes before replacing the brake shoes.

0.5 Troubleshooting 0.22

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MARCH 1996

Maintenance See individual sections on transmission, electrical, hydraulic and frame for troubleshooting.

0.6 Component removal and installation See individual sections on transmission, electrical, hydraulic and frame for troubleshooting.

0.7 Component repair See individual sections on transmission, electrical, hydraulic and frame for component repair.

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0.23

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MARCH 1996

1.0 Transmission

MARCH 1996

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1.1

Transmission HANDLE STEM ASSEMBLY

ITEM # NAME 1 2 3 4 5 6

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Ring, retainer Nut, clip Clamp Screw, cap Sheave Pin

# FOR ASSY. 2 1 1 1 1 1

ITEM # NAME 7 8 9 10 11

Handle, lower Tube, plastic Spring Link, connector Chain

# FOR ASSY. 1 1 1 1 1

MARCH 1996

Transmission TRANSMISSION ASSEMBLY PART # I

ITEM #

NAME

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

Screw, socket Cover, brake Spring, brake Rod, brake Nut, jam Yoke assembly Anchor, brake spring Key Nut, flanged(30-35 ft./lbs.)

Drum, brake Brake assembly Cam Plate Lever Clip Spring Shoe, brake Screw, socket Screw, socket Nut

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# FOR ASSY.

ITEM #

NAME

5 1 1 1 1 1 1 1 2 1 1 1 1 1 1 2 2 4 2 1

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

Washer, seal retainer Seal, felt (small) Seal, felt (large) Ring, seal retainer Nut, jam Anchor, chain Plate, guard Screw, cap Clamp Bracket, brake switch Bushing Pin, roll Cam Screw, hex locking Bearing Bolt, special Retainer Arm, brake Transmission assembly

# FOR ASSY. 1 1 1 1 1 1 1 5 2 1 2 1 1 1 1 1 1 1 1

1.3

Transmission TRANSMISSION ASSEMBLY PART # II

TORQUE NUT TO 250 FT./LBS. WHILE TURNING WHEEL.

ITEM # NAME 40 41 42 43 44 45 46 47

1.4

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Screw, socket head Case, gear Pin, dowel Key Gear, pinion Nut, flange (30-35 ft./lbs.)

Cover, gear Plug, fill/level pipe

# FOR ASSY. 16 1 2 1 1 1 1 1

ITEM # NAME 48 49 50 51 52 53 54

Washer, sealing Bearing Set, gear Bearing Ring Seal Nut, axle (250 ft./lbs.)

# FOR ASSY. 1 2 1 2 1 1 1

MARCH 1996

Transmission 1.2 SYSTEM OPERATION The PMX\QMX 12 volt and 24 volt pallet trucks use the same transmission. This transmission is a double reduction 22:1 gear ratio. The gears are a combination of helical and straight cut gears for strength and low noise. The final drive gear is mounted on opposing tapered roller bearings and the intermediate gear is mounted on ball bearings.

Gears and bearings are enclosed in an oil filled case. The drive motor is mounted externally with the drive motor pinion gear mounted on the armature shaft. The brakes are on the drive motor.

1.3 SPECIFICATIONS Gear Ratio Oil Type Oil Capacity Drive Tire Size

22:1 GL5 85W90 Approximately 1 quart 10.5" x 5" x 6.5"

1.4 MAINTENANCE AND ADJUSTMENTS BRAKE THEORY OF OPERATION The brake in your truck is a spring applied and mechanically released design. The brake has a drum that is mounted on the drive motor armature shaft. This design gives excellent braking and long life since the drum and shoes are protected from dirt and other abrasive materials. Braking is accomplished by spring on cam arm. The cam forces the brake shoes against brake drum. This action clamps the brake shoes against drum and provides braking any time handle is in the static position (i.e. fully raised or lowered).

When brake is released the cam arm forces the cam to twist, springs on the brake shoes pull the brake shoes away from brake drum. This releases brake and allows the drum to turn with the drive motor armature shaft.

BRAKE ADJUSTMENT 1. Disconnect battery and block drive wheel off floor and remove drive motor cover.

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1.5

Transmission 2. Fully raise the control handle, remove the brake application spring. This will allow the brakes to release.

3. Lower the control handle to the operating position so that brake linkage is on top of operating cam.

4. Adjust clevis so that pin just goes in brake lever.

5. Re-install spring and test braking ability. Truck should stop in its own length, if brakes are inadequate, then shorten the linkage on clevis to get adequate braking.

The brake drum may be removed and the operating lever moved one “spline” to compensate for brake shoe wear.

TRANSMISSION PIVOT BEARING ADJUSTMENT Use Loctite Thread Lock 42 on nut and install nut on transmission pivot tube. The nut should be tightened until all end play is removed from pivot bearings. The transmission must be moved during tightening of the bearing in order to seat the bearing.

1.5 TROUBLESHOOTING Because of the uncomplicated nature of this transmission, troubleshooting is limited to identifying whether problems are mechanical or electrical in nature. Fluid leaks are obviously mechanical in nature and can be found by visual inspection.

Unusual noise and/or slow running could be mechanical or electrical in nature. Generally speaking, if the problem is caused internally in the transmission then metal contamination will be evident in the oil. If there is a mechanical problem outside of the transmission then it will become evident by inspecting the drive motor and brakes.

1.6

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MARCH 1996

Transmission 1.6 Component Removal and Installation 1.6.1Transmission Removal and Installation REMOVAL 1. Disconnect the battery and remove from truck.

Block truck with drive tire off floor (about 1 inch).

2. Remove sheet metal cover and plastic cover from truck.

3. Disconnect control wiring harness and power cables from electrical panel.

4. Use spanner to remove pivot bearing retaining nut.

Transmission assembly may fall free from mounting.

5. Remove transmission assembly by lowering through mounting bracket.

6. Remove control wiring harness and power cable through transmission pivot mount.

INSTALLATION 1. Install bearing cups in mounting bracket.

NOTE: Pack the bearings with gun grease before installing.

2. Install larger of the felt seals over pivot tube on top of transmission assembly and install bearing cone.

3. Pull control wiring harness and power cables up through transmission pivot mount.

4. Install transmission assembly through transmission mounting bracket. Install smaller bearing cone and felt seal.

5. Use Loctite Thread Lock 42 on nut and install nut on transmission pivot tube. The nut should be tightened until all end play is removed from pivot bearing.

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1.7

Transmission 6. Lower truck and connect battery, turn key switch “ON” and test operation of truck.

7. Lube transmission pivot bearings with gun grease while slowly rotating the transmission.

Only fill the space between the bearings.

8. Install sheet metal cover and plastic cover on truck.

1.6.2 Drive Wheel Removal and Installation REMOVAL The drive wheel can be removed without removing the transmission by following these steps: 1. Disconnect the battery, block truck with drive tire off floor (about 1 inch).

2. Remove drive tire by hand or if wheel is stubborn use three bolts from side cover over drive tire and thread in hub to push drive tire off drive axle.

3. Press drive tire from wheel hub.

INSTALLATION 1. Press drive tire in wheel hub.

Torque to 250 ft./lbs 2. Install drive tire. ALWAYS USE A NEW NUT. The drive tire retaining nut should be torqued to 250 ft./lbs.

1.8

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MARCH 1996

Transmission 1.6.3 Axle Seal Removal and Installation REMOVAL The drive axle seal can be repaired without removing the gear case cover by following these steps: Before starting disassembly of any parts thoroughly clean out side of assembly with solvent or other non-corrosive cleaning fluid. Air dry all parts.

1. Drain transmission oil.

2. Disconnect the battery, block truck with drive tire off floor (about 1 inch).

3. Remove side cover over drive tire.

4. Remove drive tire by hand or if wheel is stubborn use three bolts from side cover over drive tire and thread in hub to push drive tire off drive axle.

5. Remove toe guard.

6. Remove axle seal with seal puller or pry out with pry bar. Take care not to damage sealing surface or mounting bore.

INSTALLATION 1. Check thread on hub and nut for damage.

2. Install new oil seal.

3. Install toe guard and drive tire. The drive tire retaining nut should be torqued to 250 ft./lbs.

4. Install side cover over drive tire.

Torque to 35 ft./lbs.

5. Lower truck off blocks.

6. Refill transmission case with new oil.

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1.9

Transmission 1.6.4 Brake Linkage Removal and Installation REMOVAL 1. Disconnect battery and block truck with drive tire “OFF” floor (about 1 inch).

2. Remove side cover over drive tire.

3. Loosen brake interlock switch and slide switch away from cam of brake arm.

4. Disconnect main spring and brake linkage at clevis and remove entire lever from case.

INSTALLATION 1. Thoroughly clean all parts with solvent or other non-corrosive cleaning fluid. Air dry all parts.

2. Install brake linkage and stretch spring across mounting.

3. Adjust brake linkage and brake interlock switch (see adjustment section of the manual).

4. Install the side cover over drive tire.

Torque to 35 ft./lbs.

5. Remove blocks, connect battery and test operation of unit.

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MARCH 1996

Transmission 1.6.5 Brake Shoe Removal and Installation 1. Disconnect battery and block truck with drive tire “OFF” floor (about 1 inch).

2. Remove side cover over drive tire.

3. Disconnect main spring of brake.

4. Move control handle to “BRAKE-RELEASED” position and disconnect clevis from brake lever.

5. Loosen nut and remove brake drum.

6. Lift one shoe at a time to center to remove mounting bolts.

During reassembly the brake lever should be checked to see that it is set at 60, and that brake drum nut is torqued to 30 ft./lbs.

Adjust brake linkage and brake interlock switch (see adjustment section of this manual).

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1.11

Transmission 1.7 Component Repair 1.7.1 Transmission Disassembly & Assembly DISASSEMBLY After draining gear case lubricant, thoroughly clean outside with solvent or other non-corrosive cleaning fluid. Air dry all parts and proceed with disassembly of transmission as follows: 1. Remove transmission from truck.

2. Remove gear case cover.

3. Block transmission with gear case side down.

Allow room for gears to drop between blocks.

4. Press drive axle through collar and bearing.

Drive axle and intermediate gear will come out together.

5. Remove old bearings and races from gears and case. Clean transmission case.

1.12

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MARCH 1996

Transmission ASSEMBLY Heat bearing cone on bearing heater to facilitate installation.

1. Install new bearings on intermediate gear.

2. Install new inner bearing cone on drive axle.

3. Install new bearing cups in transmission case.

4. Position transmission on work bench with gear case side up. Place drive axle and intermediate gear in case as a unit with gears meshed.

Because of gear size and bearing interference these pieces cannot be installed separately.

5. Use Loctite #515 “gasket eliminator” on mating surface and install gear case side covers. Be sure that two dowel pins are in case to position cover. Torque cover bolts to 30 ft./lbs.

6. Reposition transmission case so that it rests on gear case cover.

7. Temporarily install drive motor in transmission case using only two bolts to hold motor in place.

8. Install outer drive axle bearing cone and retaining collar: a. Place bearing cone over shaft. Use a standard M24 nut and bearing installation tool to push bearing on drive axle. At this time the bearing will not seat on shoulder of drive axle. Remove nut and pusher. b. Install drive axle seal in transmission case. c. Install collar on drive axle. Use bearing installation tool and nut to press collar on shaft. This should also press bearing down to seat on shoulder. Turn axle shaft while you torque nut to 250 ft./lbs. Control the drive axle turning by holding brake lever on drive motor.

9. Transmission assembly is now complete.

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1.13

Transmission Reinstall control handle and install transmission in truck. The drive motor will have to be removed in order to route electric cables and control wiring through pivot tube. Liberally grease top and bottom bearing cones on pivot bearing. Bottom cup of pivot bearing is a slip fit in mounting frame, be certain that bearing cup has not fallen out of frame.

10. Torque pivot bearing retaining nut.

See adjustment section.

1.14

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MARCH 1996

2.0 ELECTRICAL

MARCH 1996

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2.1

Electrical 2.1 Component Identification PMX 12 volt uses a Curtis® PMC transistor controller to supply power to the series wound drive motor.

PMX 24 volt uses the “Prime-Drive 200" contactor free transistor control to supply power to a separately excited drive motor.

QMX 24 volt uses the “Prime-Drive 200 HS” contactor free transistor control to supply power to a separately excited drive motor. Both systems allow the operator infinitely variable speed control.

ELECTRICAL SCHEMATIC SYMBOLS

DOUBLE TIP CONTACTOR

DIODE

SINGLE TIP CONTACTOR

CAPACITOR

COIL

THERMAL PROTECTOR

CONTROL SWITCH

RESISTOR T1

T2

PLUG

TRANSFORMER T3

FUSE

ARM

T4 ELECTRICAL LINE JOINTING

ARMATURE ELECTRICAL LINE CROSSING

S1 FIELD S2

2.2

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MARCH 1996

Electrical

PMX 12 VOLT ELECTRICAL SCHEMATIC

ELECTRICAL SCHEMATIC, 12 VOLT PMX

MARCH 1996

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2.3

Electrical ELECTRICAL ASSEMBLY, 12 VOLT PMX

2.4

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MARCH 1996

Electrical ITEM # NAME 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 15 15 16 17 18

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Panel assembly Motor, drive Pump, lift Cable Cable Screw, thread form Plug, diode Screw, Socket flat head Screw, thread form Switch, emergency disconnect Mount Harness, wire Tie, cable Tie, cable Switch, brake Screw, machine Nut, twin Switch, key Lift Interrupt & Gauges Fuse, 10 AMP

# FOR ASSY. 1 1 1 2 4 3 2 2 2 1 1 1 3 5 1 2 1 1 1 1

2.5

Electrical PANEL ASSEMBLY, 12 VOLT PMX

ITEM # NAME 1 2 3 4 5 6 7 7 7 8 8 9 2.6

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Panel Connector assembly Breaker, circuit Contactor, line Controller Nut Switch, lift limit Screw, machine Nut, twin Relay Screw, cheese head Bar, bus

# FOR ASSY.

ITEM #

NAME

1 1 1 1 1 4 1 2 1 1 2 1

10 11 12 13 14 15 16 17 18 19 20

Screw, poxidriv Resistor assembly Horn Bar, bus Bar, bus Bar, bus Lockwasher Decal Screw, locking Screw, thread form Contactor, F & R

# FOR ASSY. 4 1 1 1 1 1 4 1 4 8 1

MARCH 1996

Electrical FORWARD & REARWARD CONTACTOR ASSEMBLY, 12 PMX

ITEM # NAME 1K 2K 3 4K 5K 6K 7 8 9K

Nut Lockwasher Bar, bus Cover assembly Spring Bridge assembly Nut Lockwasher Bar, bus

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# FOR ASSY. 4 4 1 2 2 2 4 4 4

ITEM # NAME 10K 11 12 13 14K 15 16 K

Cover Coil, magnet Washer, flat Screw, cap Bar, bus Bar, bus Screw, machine Kit, contact (Contains Items Marked with “K”)

# FOR ASSY. 1 1 2 2 4 4 2 1

2.7

Electrical 2.2 System Operation 12 volt PMX The 12 volt PMX uses a Curtis® PMC transistor controller to supply power to the series wound drive motor. This allows the operator infinitely variable speed control. The lift and lower functions are directly controlled by the operator.

Power circuits are protected against overload with an automatic resetting circuit breaker and control circuits are protected with replaceable fuses.

These trucks are equipped with key switches for security, emergency disconnect for safety and brake interlock switches to prevent drive operation if the brakes are applied.

During normal operation the following circuits are activated.

Battery connected and emergency disconnect push button switch pulled out to “run” position.

Battery positive voltage will be available via the battery positive cable, battery connector, power cable, 110 amp circuit breaker and buss bar to the positive side of the line contactor and from the positive side of the line contactor via a power cable to the positive side of the lift pump contactor. Since neither contactor is energized no current is flowing.

Battery voltage is also available from the positive side of the 110 amp circuit breaker via wire #28, 10 amp control fuse, wire #26, emergency disconnect push button switch, and wire #27 to positive side of the key switch and battery discharge indicator input on optional BDI/HM. Because the BDI/HM display is connected directly to battery negative via wire #13 the battery discharge indicator will be illuminated to indicate the state of the battery charge.

Key switch turned "ON" With the key switch turned “ON” positive battery voltage is available via the key switch and wire #6 to the brake interlock switch. Because the control handle is not pulled down and the brakes are not released the brake interlock switch will be open and no current will flow.

2.8

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MARCH 1996

Electrical Positive battery voltage is also available via the key switch and wire#6 to the lift, lower, and horn switches in the control handle.

Control handle pulled down; brakes released and brake interlock switch closed.

With the brake interlock switch closed positive battery voltage will be available via wire #7 to the line contactor coil. Wire #13, battery negative, is connected to the other side of the line contactor coil therefore the line contactor coil is energized and the line contactor will close.

Positive battery voltage is also available via wire #7 to the directional control switches and to terminal #1 on the Curtis® PMC controller.

When the line contactor closes positive battery voltage is available through the line contactor to the B+ terminal on the Curtis® PMC controller and to the A1 terminal on the drive motor.

Although the truck is not moving the Curtis® PMC controller has been turned on to recognize SRO signal inputs.

If the truck is equipped with the optional Battery Discharge Indicator and Hourmeter combination gauge then wire #7 will supply positive battery voltage to start the hour meter when the control handle is pulled down and the brake interlock switch is closed.

Reverse travel (fork direction) switch is closed.

When the reverse switch is closed to make the truck travel in the fork direction positive battery voltage is made available via wire #3 to the reverse contactor coil. Wire #13, battery negative, is connected to the other side of the reverse contactor coil. Therefore, the reverse contactor coil is energized and the reverse contactor will close.

At this time the Curtis® PMC controller will start “pulsing” power to the drive motor at a rate based on the accelerator potentiometer position. The PMC power circuit and the accelerator potentiometer circuit are described later.

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2.9

Electrical Forward travel (control handle direction) switch is closed.

When the forward switch is closed to make the truck travel in the control handle direction positive battery voltage is made available via wire #2, a set of normally closed contacts on RE2, and wire #32 to the forward contactor coil. Wire #13, battery negative, is connected to the other side of the forward contactor coil, therefore, the forward contactor coil is energized and the forward contactor will close.

At this time the Curtis® PMC controller will start “pulsing” power to the drive motor at a rate based on the accelerator potentiometer position. The PMC power circuit and the accelerator potentiometer circuit are described later.

Curtis® PMC controller power circuits.

When either the forward or reverse contactors are closed current will flow from the battery positive terminal through the battery cable, through the 110 amp circuit breaker, through the line contactor to the B+ terminal on the Curtis® PMC controller. From the B+ terminal through the drive motor armature, A1 to A2, through the normally open (now closed) contacts of the chosen direction contactor; through the drive motor field coils (S1 to S2 or S2 to S1 depending on direction), through the normally closed contacts of the opposite direction contactor, to the M- terminal of the Curtis® PMC controller.

The current flowing into the M- terminal will be connected internally in the Curtis® PMC controller to the B- terminal which is connected directly to the battery negative terminal.

Inside the Curtis® PMC controller a high power semi-conductor switch, consisting of an array of paralleled power MOSFET transistors, controls the current through the drive motor. The transistors are turned on and off at the rate of 15,000 times per second by the control circuitry, while the ratio of the on and off times is regulated by the input of the accelerator potentiometer. This is called Pulse Width Modulation. When the transistors are on, current flows through the drive motor and builds up energy in the motor's magnetic field. When the 2.10

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MARCH 1996

Electrical transistors turn off, this stored energy continues to flow in the drive motor through the freewheel, or flyback diode. Thus, the average motor current is greater then the average battery current and smooth, step less control of the power delivered to the drive motor is achieved with very little power loss in the control components.

Accelerator Potentiometer Circuits The accelerator potentiometer is used to signal the Curtis® PMC controller of the desired motor speed.

By controlling the position of the accelerator potentiometer the operator can control the travel speed of the truck.

The accelerator potentiometer is connected between terminals 2 and 3 on the Curtis® PMC controller. When in neutral the resistance through the accelerator potentiometer is high, approximately 5000 ohms. As the truck controls are operated to a higher travel speed the resistance through the accelerator potentiometer decreases.

The resistance should decrease to below 50 ohms at full speed.

The resistance of the accelerator potentiometer is used to regulate the voltage potential on terminals 2 and 3 of the Curtis® PMC controller. In neutral with a high resistance through the accelerator potentiometer the voltage potential, with respect to battery negative will be 1.85 volts +/- 10% on terminal 3 and 5.20 volts +/- 10% on terminal 2.

When the controls are operated to high speed and the resistance through the accelerator potentiometer is at a minimum the voltage potential, with respect to battery negative, will equalize at 4.3 volts +/- 10% on both terminals 2 and 3.

Because the accelerator potentiometer is not polarity oriented it does not matter which lead of the potentiometer is connected to either terminal 2 or 3.

The accelerator potentiometer is used to control the speed of the truck during normal operation. When the red emergency reverser switch in the control handle is pushed the accelerator potentiometer is bypassed and terminals 2 and 3 on the Curtis® PMC controller are connected directly with a set of contacts in RE2.

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2.11

Electrical Emergency Reverser Switch When the red button on the end of the control handle is depressed the emergency reverser switch is activated. This switch will close and battery voltage is supplied to the coil of RE2 causing RE2 to energize, and to the reverse contactor coil, and the reverse contactor will close.

When RE2 energizes the lower set of contacts closes to directly connect the accelerator potentiometer circuit terminals 2 and 3 on the Curtis® PMC controller. This gives the controller the signal for full speed when the red emergency reverser button is activated.

When RE2 energizes the upper set of contacts opens on one side to break the connection between the forward direction switch wire #2 and the forward contactor coil wire #32. This causes the forward contactor to de-energize and open. The other side of the upper contact in RE2 will close a connection between the forward direction switch wire #2 and the coil of RE2 wire #18. This will cause RE2 to remain energized even after the red emergency reverse switch is release, as long as the forward direction switch is closed. The purpose of this is to make it necessary to return the control handle to neutral before the truck can be driven again after the red emergency reverser has been activated.

Lift Pallet Forks When the lift switch bar is pushed the lift switch closes and positive battery voltage is supplied via wire #5 to the lift limit switch. When the pallet forks are below their fully raised height the lift limit switch is closed and voltage is supplied via wire #17 to the lift contactor coil. The other side of the lift contactor coil is connected to battery negative via wire #13 and so the lift contactor coil energizes and the contactor closes.

If the truck is equipped with the optional lift interrupt system then the negative wire from the lift contactor coil is connected to the BDI/HM/Lift interrupt gauge.

If the battery voltage is above the lift interrupt threshold voltage then the lift contactor coil negative is connected to battery negative internally through the gauge/controller. If the battery voltage is below 2.12

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MARCH 1996

Electrical the lift interrupt threshold voltage then the lift contactor coil negative will not be connected to battery negative inside the gauge/controller.

When the lift contactor closes positive battery voltage is supplied through the 110 amp circuit breaker and the lift contactor to the lift motor. The other side of the lift motor is connected to battery negative and so the motor starts running and the lift pump rotates.

When the pump motor runs the pallet forks will raise. When the pallet forks reach their maximum raised height the lift limit switch will be activated and open the connection between the lift switch and the lift contactor coil. The lift contact will open and the lift motor will turn off.

Lower pallet forks When the lowering switch bar is pushed the lowering switch closes and positive battery voltage is supplied to the lowering solenoid valve coil. The other side of the coil is connected directly to battery negative via wire #13 and so the solenoid valve energizes to release the oil in the lift cylinders, and the pallet forks lower.

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2.13

Electrical

PMX 24 VOLT ELECTRICAL SCHEMATIC

ELECTRICAL SCHEMATIC, 24 VOLT “E” & “EE” PMX

2.14

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MARCH 1996

Electrical ELECTRICAL SCHEMATIC SYMBOLS

DOUBLE TIP CONTACTOR

DIODE

CAPACITOR

SINGLE TIP CONTACTOR

COIL

THERMAL PROTECTOR

CONTROL SWITCH

RESISTOR

T1

T2

PLUG

TRANSFORMER T3

T4

FUSE ELECTRICAL LINE JOINTING

ARM

ARMATURE ELECTRICAL LINE CROSSING

S1 FIELD S2

MARCH 1996

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2.15

Electrical ELECTRICAL ASSEMBLY, 24 VOLT PMX

2.16

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MARCH 1996

Electrical ITEM # NAME 1 2 3 4 5 6 7 8 9 10 11 12 13 13 13 14 15 16 17 18 19 20

MARCH 1996

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Panel assembly Motor, drive Pump, lift Cable Cable Screw, thread form Screw, thread form Screw, flat head socket Screw, thread form Switch, emergency disconnect Mount Harness, wire Switch, brake Screw, machine Nut, twin Harness, field Decal, controller Fuse, 10 AMP Tie, cable Tie, cable Lift Interrupt & Gauge Switch, key

# FOR ASSY. 1 1 1 2 2 2 1 2 2 1 1 1 1 2 1 1 1 1 5 2 1 1

2.17

Electrical PANEL ASSEMBLY, 24 VOLT “E” PMX and QMX

ITEM # NAME 1 2 3 4 5 6 6 6 7

2.18

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Panel Connector assembly Breaker, circuit Contactor, line Controller Switch, lift limit Screw, machine Nut, twin Screw, cap

# FOR ASSY.

ITEM #

NAME

1 1 1 1 1 1 2 1 2

8 9 10 11 12 13 14 15 16

Lockwasher Horn Bar, bus Bar, bus Screw, cap Lockwasher Screw, thread form Screw, thread form Decal

# FOR ASSY. 2 1 1 1 4 4 4 4 1

MARCH 1996

Electrical PANEL ASSEMBLY, 24 VOLT “EE” PMX

ITEM # NAME 1 2 3 4 5 6 6 6 7 8 9

Panel Connector assembly Breaker, Circuit Contactor, line Controller Switch, lift limit Screw, machine Nut, twin Screw, cap Lockwasher Horn

MARCH 1996

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# FOR ASSY.

ITEM #

NAME

1 1 1 1 1 1 2 1 2 2 1

10 11 12 13 14 15 16 16 17 18 19

Bar, bus Screw, cap Lockwasher Screw, thread form Screw, thread form Decal Lid, “EE” box Box, “EE” Cable assembly Relief, strain Screw, flat head

# FOR ASSY. 1 4 4 3 4 1 1 1 1 4 4

2.19

Electrical

QMX 24 VOLT ELECTRICAL SCHEMATIC

ELECTRICAL SCHEMATIC, 24 VOLT QMX

2.20

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MARCH 1996

Electrical ELECTRICAL SCHEMATIC SYMBOLS

DOUBLE TIP CONTACTOR

DIODE

CAPACITOR

SINGLE TIP CONTACTOR

COIL

THERMAL PROTECTOR

CONTROL SWITCH

RESISTOR

T1

T2

PLUG

TRANSFORMER T3

T4

FUSE ELECTRICAL LINE JOINTING

ARM

ARMATURE ELECTRICAL LINE CROSSING

S1 FIELD S2

MARCH 1996

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2.21

Electrical ELECTRICAL ASSEMBLY, QMX

2.22

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MARCH 1996

Electrical ITEM # NAME 1 2 3 4 5 6 7 8 9 10 11 12 13 13 13 14 15 16 17 18 19 20 20 21

MARCH 1996

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Panel assembly Motor, drive Pump, lift Cable Cable Screw, thread form Screw, thread form Screw, flat head socket Screw, thread form Switch, emergency disconnect Mount Harness, wire Switch, brake Screw, machine Nut, twin Harness, field Decal, controller Plug, resistor Tie, cable Tie, cable Fuse, 10 AMP Switch, key Switch, toggle Lift Interrupt & Gauge

# FOR ASSY. 1 1 1 2 2 2 1 2 2 1 1 1 1 2 1 1 1 1 1 5 2 1 1 1

2.23

Electrical 24 VOLT PMX The 24 volt PMX uses the “Prime-Drive 200” contactor free transistor control to supply power to a separately excited drive motor. The 24 volt QMX uses the “PrimeDrive 200 HS” contactor free transistor control to supply power to a separately excited drive motor. This allows the operator infinitely variable speed control. The lift and lower functions are directly controlled by the operator.

Power circuits are protected against overload with an automatic resetting circuit breaker and control circuits are protected with replaceable fuses.

The trucks are equipped with key switches for security, emergency disconnect switches for safety, and brake interlock switches to prevent drive operation if the brakes are applied.

During normal operation the following circuits are activated: Battery connected and emergency disconnect push button switch pulled out to “run” position.

Battery positive voltage will be available via the battery positive cable, battery connector, power cable, 110 amp circuit breaker, and buss bar to the positive side of the line contactor and from the positive side of the line contactor via a power cable to the positive side of the lift pump contactor. Since neither contactor is energized no current is flowing.

Battery voltage is also available from the positive side of the 110 amp circuit breaker via wire #28, 10 amp control fuse, wire #26, emergency disconnect push button switch, and wire #27 to the positive side of the key switch and to the “Prime-Drive 200" controller Z plug pin position 1, (PZ-1). The “N” terminal of the “Prime-Drive 200" controller is connected directly to battery negative and so the controller turns on to recognize SRO signal inputs and the 1C capacitor will be charged.

If the truck is equipped with the optional Battery Discharge Indicator/Hour Meter combination gauge or with the BDI/HM with Lift Interrupt multi-function gauge then battery voltage will be supplied via wire #27 to the gauge. The gauge is connected directly 2.24

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MARCH 1996

Electrical to battery negative and the hour meter display will be illuminated to show the total elapsed hours. The hour meter will not be clocking additional hours at this time.

Key switch turned “ON” With the key switch turned “ON” positive battery voltage is available via the upper contacts in the key switch and wire #6 to the brake interlock switch.

Because the control handle is not pulled down and the brakes are not released the brake interlock switch will be open and no current will flow.

The lift, lower, and horn switches in the control handle receive positive battery voltage via wire #6.

Positive battery voltage is also available via wire #6 through the normally closed reverser switch and wire #11 to the “Prime-Drive 200" controller Z-plug, pin position 8. (PZ-8) If the truck is equipped with the optional BDI/HM or BDI/HM with Lift Interrupt then wire #6 will supply positive battery voltage to the gauge and the battery indicator LED segment will be illuminated.

Control handle pulled down; brakes released and brake interlock switch closed.

With the brake interlock switch closed positive battery voltage will be available via wire #7 to the “Prime-Drive 200" controller Z-plug, pin position 2.

(PZ-2) The controller logic then makes the following start-up checks before the controller is allowed to operate: 1) Insures that the voltage at A2 is between 12 percent and 88 percent of battery volts. This checks for shorted 3 REC and/or power transistors.

2) Checks for open F and R switch inputs. Voltage at PZ-6 and PZ-7 should be 0 volts.

3) Checks for accelerator volts at PZ-9 to be greater then 2.5 volts.

4) Checks for closed emergency reversal switch.

Voltage at PZ-8 should be at battery volts.

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2.25

Electrical If all of the above start-up checks are satisfied and the capacitor is fully charged, the logic will activate a driver module to connect PZ-4 and thus the line contactor coil, wire #24, to battery negative.

A momentary positive voltage is supplied to the line contactor coil, wire #33, from the 1C capacitor via the “P” terminal on the controller, wire #29, and the lower contacts in the key switch. This is enough current to energize the contactor coil and cause the line contactor to close. With the line contactor closed positive voltage is supplied through the line contactor to the “P” terminal on the controller and to wire #29, key switch lower contacts and wire #33 to the line contactor coil to keep it energized.

With the brake interlock switch closed positive battery voltage is also supplied via wire #7 to the direction control switches in the control handle.

If the truck is equipped with the optional BDI/HM or BDI/HM with Lift Interrupt then wire #7 will supply positive battery voltage to start the hour meter when the control handle is pulled down and the brake interlock switch is closed.

The line contactor will open 15 seconds after the control handle is raised and the brake interlock switch is opened.

Reverse travel (fork direction) switch is closed.

When the reverse switch is closed to make the truck travel in the fork direction positive battery voltage is made available via wire #3 to the “Prime-Drive 200" controller, PZ-7.

This input to the controller will energize the controller power circuits and accelerator potentiometer circuits. Operation of these circuits will be covered later.

Forward travel (control handle direction) switch is closed.

When the forward switch is closed to make the truck travel in the control handle direction positive battery voltage is made available via wire #2 to the “PrimeDrive 200" controller, PZ-6.

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Electrical This input to the controller will energize the controller power circuits and accelerator potentiometer circuits. Operation of these circuits will be covered later.

"Prime-Drive 200" controller power circuits.

BASICS OF CIRCUIT OPERATION The “Prime-Drive 200" controller is actually two controls in one. There is a field winding controller section which not only regulates the voltage and current applied to the field circuit but also lets you determine the direction of motor rotation. Along with the field control there is an armature controller section which regulates the voltage and the current applied to the armature circuit. The control is energized by plugging in the battery. A capacitor charging circuit charges capacitors (1C) to battery volts in approximately 2 seconds. When the key and brake switches are closed, the logic then make the following start-up checks before the control is allowed to operate: 1) Insures that the voltage at A2 is between 12 percent and 88 percent of battery volts. This checks for shorted 3 REC and/or power transistors.

2) Checks for open F and R switch inputs. Voltage at PZ-6 and PZ-7 should be 0 volts.

3) Checks for accelerator volts at PZ-9 to be greater then 2.5 volts.

4) Checks for closed emergency reversal switch.

Voltage at PZ-8 should be at battery volts.

If all the above start-up checks are satisfied and the capacitor 1C is fully charged, the line contactor will close and normal vehicle operation can begin.

Selecting either the forward or reverse direction will energize the proper directional transistors in the field control circuit. The card then supplies gate voltage to the power transistors, turning them on.

Current flows from the battery through the motor armature, power transistors back to battery negative. When gate voltage at the transistors is removed, they turn off. during the off time, the MARCH 1996

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2.27

Electrical energy stored in the motor, by virtue of the motors inductance, will cause current to circulate through the motor around the loop formed by 3REC providing what is called flyback current. The battery current continues to flow from battery positive through 1C to negative during the entire off time due to the high frequency of oscillation. The control converts battery current at battery voltage into a higher motor current at lower motor volts. This is why measured motor current will be greater then battery current except when the control is operating at 100% on time.

The time for the next ON and OFF cycle to start is determined by the time the control card takes to oscillate. This frequency of oscillation is controlled by the speed input signal from the accelerator and circuitry in the card. Slow speed is obtained by having maximum ohms or volts from the speed input signal. As the resistance or voltage decreases, the speed of the motor increases. The transistor circuit is capable of delivering approximately 100%battery volts.

Figure 1 and 2 show battery and motor current paths in the armature circuit during the ON and OFF times for a typical running condition of 100 amps motor 50% on time (half speed).

CONTROL FEATURES OSCILLATOR - The oscillator section of the card has two adjustable features. With the accelerator at maximum ohms or volts, the creep speed can be adjusted by a trimpot. The field control section allows the adjustment of the field weakening level in order to set the top speed of the motor. This top speed function (Minimum Field Current) is enabled when the armature current is less then 85 amps and the accelerator input voltage is less then 1 volt. Top Speed can be adjusted by a trimpot.

The % ON time has a range of approximately 0 to 100 percent. The controller operates at a constant frequency and the percent on time is controlled by the pulse width of the voltage/current applied to the motor circuits.

PLUGGING - slows the vehicle to a stop when reversing, by providing a small amount of retarding 2.28

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Electrical torque for deceleration. The oscillator circuit regulates braking at an adjustable plug current limit level to bring the truck to a smooth stop and reversal.

PEDAL POSITION PLUG - regulates plugging distance based on accelerator position. Maximum plug current is obtained with the accelerator in the top speed position.

CONTROLLED ACCELERATION AND 1A TIME allows for adjustment of the rate of time it takes for the control to accelerate to 96% applied battery voltage to the motor on hard acceleration.

ACCELERATOR VOLTS HOLD-OFF - checks the voltage level at the accelerator input whenever the brake interlock switch is activated. If the voltage is less then 2.5 volts the control will not operate. This is to insure low speed operation at start up.

STATIC RETURN TO OFF (SRO) - If the brake interlock or key switch is opened, the control will shut off and cannot be restarted until directional lever is returned to neutral.

PULSE MONITOR TRIP (PMT) - The PMT circuit will not allow the control to start if the main transistors are shorted (uncontrolled top speed condition); the control will not allow the line contactor to close.

The PMT circuit will shut down operation of the control (opening of the line contactor), if the main transistors fail to shut off. When the PMT circuit prevents the line contactor from closing, the PMT circuit can be reset only by opening the key switch.

THERMAL PROTECTOR (TP) - This is a temperature sensitive device that is mounted inside the transistor module. If the transistor temperature begins to exceed the design limits, the thermal protector will lower the maximum current limit and not allow the device to exceed its temperature limits.

As the panel cools, the thermal protector will automatically return the control to full power.

REVERSE BATTERY PROTECTION - An external line contactor protects the control if the battery connections are reversed. Proper operation will begin when the connections are corrected.

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2.29

Electrical SHORTED 3REC PROTECTION - prevents the control from operating if the flyback diode (3REC) is in a shorted condition.

SHORTED CAPACITOR PROTECTION - prevents the line contactor from closing if the capacitor are shorted.

CONTROLLED CAPACITOR PRE-CHARGE - An external line contactor prevents high in-rush current which could cause battery plug damage.

LOW CURRENT CONTROL SWITCHES - are used for the directional input, speed limit, emergency reversal, and brake switches. The only coil current carrying switch is the key switch and this switch does not close under load.

COIL DRIVE MODULES AND COIL SUPPRESSION - the drivers are internal to the logic card and are current limited for short circuit protection. These drivers open or close these coils on command from the logic card.

LOW VOLTAGE - Batteries under load, particularly if undersized or more then 80 percent discharged, will produce low voltages at the transistor control terminals. The control is designed for use down to 16V. Lower battery volts may cause the control to mis-operate; however the PMT will open the line contactor when battery volts drop below 16 volts.

HIGH FREQUENCY OPERATION - The high oscillation rate of the control allows quieter operation, higher average motor current with lower peak motor currents, less ripple current at the motor, and less motor heating.

FIELD WEAKENING - Field weakening is a method of attaining higher running speeds for the vehicle in level operation. The field coils are separately excited from the armature coils with the “PrimeDrive 200" controller.

REGENERATIVE BRAKING - is activated when the vehicle is moving and the directional lever is moved from one direction to the other. This initiates a plugging signal by reversing the motor field. Once the generated current reaches a particular current level, the plugging mode transitions to regenerative 2.30

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Electrical braking mode. The control will remain in regenerative mode as long as the regen current can maintain regenerative current limit. When the regenerative current cannot be maintained and drops below the level set, the regenerative braking mode transitions back to plugging mode. The major advantage of regen is longer motor life due to reduced motor heating.

Emergency Switch

Closed

Disabled

Open Brake Switch

Open

Disabled

EMERGENCY REVERSAL CIRCUIT - If the Emergency Reversal button is opened the control automatically plugs to a stop and re-accelerates in the reverse direction until the reversal switch is released. At this time, the control is inoperable. If the emergency reversal switch is again opened, the control will allow a reversal again but normal control operation will not be restored until the directional switch is recycled and the SRO requirements are met.

The Emergency Reversal Circuit operation logic is as follows: Accelerator Potentiometer Circuit

Closed Full power plug and controlled acceleration

The accelerator potentiometer is used to signal the “Prime-Drive 200" controller of the desired motor speed. By controlling the position of the accelerator potentiometer the operator can control the travel speed of the truck.

The accelerator potentiometer is connected between terminal PZ-9 and battery negative. When in neutral the resistance through the accelerator potentiometer is high, approximately 5000 ohms. As the truck controls are operated to a higher travel speed the resistance through the accelerator potentiometer decreases. The resistance should decrease to below 50 ohms at full speed.

The resistance of the accelerator potentiometer is used to regulate the voltage on PZ-9. In neutral with a high resistance through the accelerator potentiometer the voltage at PZ-9 will be approximately 3.5 volts DC positive. When the controls are operated to high speed and the resistance through the accelerator potentiometer is at a minimum the voltage at PZ-9 will be reduced to 0 volts.

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2.31

Electrical Emergency Reverser Switch When the red button on the end of the control handle is depressed the emergency reverser switch is activated. This switch will open and break the circuit supplying positive battery voltage to PZ-8 via wire #11.

Dropping voltage at PZ-8 causes the controller to automatically plug to a stop at maximum plug current and to re-accelerate in the reverse direction until the emergency reverser switch is de-activated.

If the emergency reverser switch is again opened the controller will again reverse the truck but normal operation will not be restored until the direction switch is returned to neutral and the SRO requirements are met.

Lift Pallet Forks When the lift switch bar is pushed the lift switch closes and positive battery voltage is supplied via wire #5 to the lift limit switch. When the pallet forks are below their fully raised height the lift limit switch is closed and voltage is supplied via wire #17 to the lift contactor coil. The other side of the lift contactor coil is connected to battery negative via wire #13 and so the lift contactor coil energizes and the contactor closes.

If the truck is equipped with the optional lift interrupt system then the negative wire from the lift contactor coil is connected to the BDI/HM/Liftinterrupt gauge.

If the battery voltage is above the lift interrupt threshold voltage then the lift contactor coil negative is connected to battery negative internally through the gauge/controller. If the battery voltage is below the lift interrupt threshold voltage then the lift contactor coil negative will not be connected to battery negative inside the gauge/controller.

When the lift contactor closes positive battery voltage is supplied through the 110 amp circuit breaker and the lift contactor to the lift motor. The other side of the lift motor is connected to battery negative and so the motor starts running and the lift pump rotates.

When the pump motor runs the pallet forks will raise. When the pallet forks reach their maximum 2.32

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Electrical raised height the lift limit switch will be activated and open the connection between the lift switch and the lift contactor coil. The lift contact will open and the lift motor will turn off.

Lower pallet forks When the lowering switch bar is pushed the lowering switch closes and positive battery voltage is supplied to the lowering solenoid valve coil. The other side of the coil is connected directly to battery negative via wire #13 and so the solenoid valve energizes to release the oil in the lift cylinders, and the pallet forks lower.

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2.33

Electrical 2.3 Specifications 2.3.1 Fuse and Circuit Breaker Ratings Control Fuse (replaceable) Power circuit breaker (auto reset)

10 amp 110 amp

2.3.2 Amp Draws 12 volt truck - Battery amps at top travel speed Lifting

75 amp 200 amp

24 volt truck at top travel speed Armature cable A2 45 amp maximum Field cable S2 18 amp lifting - battery amps 115 amp at hydraulic relief - battery amps 115 amp 2.3.3 Motor repair specifications 12 volt drive motor minimum brush length new brush spring tension minimum commutator diameter with new brush

.75" 32-40 oz. .75"

24 volt drive motor minimum brush length new brush spring tension minimum commutator diameter

.75" 32-40 oz.

2.625"

12 volt pump motor minimum brush length minimum commutator diameter new brush spring tension with new brush

.25" 1.5" 32-40 oz.

24 volt pump motor minimum brush length minimum commutator diameter new brush spring tension with new brush

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.25" 1.5" 32-40 oz.

MARCH 1996

Electrical 2.4 Maintenance and Adjustments 2.4.1 Maintenance The electrical system requires little maintenance.

Connections must be kept clean and tight and electrical components should be protected from moisture. Motor brushes should be inspected for minimum length at each month planned maintenance service and the motors should be cleaned using an approved compressed air blower.

If the truck is equipped with cold storage, freezer use, or corrosive environment application package then the di-electric compound in the plug-in connectors should be renewed periodically. This compound is available through the parts department of your authorized dealer.

2.4.2 Adjustments Lift Limit Switch The lift limit switch is accessible by removing the sheet metal and molded plastic shields from the front of the truck. The switch operates off a cam lobe formed into the shield mounting bracket.

To adjust switch: 1. Remove sheet metal console cover on front of truck.

2. Remove molded transmission.

plastic

cover

above

3. Loosen mounting screws and move lift limit switch away from operating cam so that it does not operate.

4. Raise pallet forks to maximum height. Do not stall hydraulics against relief for longer then necessary.

5. Lower pallet forks until the tops of the forks are 230 mm (9") above the floor.

6. Adjust lift limit switch to operate at this point and tighten mounting screws.

7. Reassemble covers and shields.

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2.35

Electrical Accelerator Potentiometer The accelerator potentiometer is accessible inside the control handle head by removing the switch plate. The accelerator potentiometer operates off a gear toothed shaft (rack) that is moved when the travel controls are twisted.

To adjust the accelerator potentiometer: 1. Disconnect the battery.

2. Remove the six (6) outside screws securing the raise/lower/horn switch plate to the control handle head. Remove the switch plate and lay it over to one side.

3. The accelerator potentiometer leads must be disconnected from the controller before connecting an ohmmeter for adjusting.

Remove the sheet metal console cover and disconnect wires #9 and #10 from the controller on the 12 volt truck. On the 24 volt truck disconnect the “Z” plug from the controller.

4. Connect ohmmeter leads to the accelerator potentiometer leads.

5. In neutral the ohmmeter reading should be 5500 to 6000 ohms and will reduce to below 50 ohms as the travel controls are operated to high speed.

6. Loosen the mounting screws for the accelerator potentiometer mounting bracket and slide bracket up or down as necessary to make adjustments. Hold the bracket snug against the handle housing while taking measurements.

If the slotted holes in the bracket do not allow enough adjustment then the bracket may be lifted slightly and the potentiometer drive gear can be rotated by one tooth.

7. Tighten bracket mounting screws reassemble switch plate and covers.

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Electrical Brake Interlock Switch The brake interlock switch is located under the drive motor cover. It is activated by the brake arm. Its purpose is to shut OFF electrical power to the drive motor when the brake is applied (handle is fully up or down) by opening the control circuit. To adjust the interlock switch: 1. Disconnect battery and block drive wheel off floor and remove drive motor cover.

2. Leave the brake “ON” (handle up).

3. Loosen the two (2) screws holding interlock switch on bracket and slide switch left, away from brake arm as far as possible.

4. Slide switch to the right until switch clicks (snaps). Next move and additional 1/32 inch and tighten screws.

5. Check that brake arm makes solid contact with the interlock switch lever.

6. Check that switch clicks (snaps) near middle of the cam arm movement. Brake switch should operate within 10° of handle movement from the full up or full down position.

7. Install drive motor cover and tighten torque to 35 ft./lbs.

8. Remove blocks, connect battery and test operation of unit.

Hourmeter with battery discharge indicator and lift interrupt The lift interrupt controller is built into the combination hourmeter and BDI gauge. On the back of the gauge are two adjusting potentiometer labeled “discharge” and “reset”. Adjustment is made by using a small screwdriver to rotate these potentiometer to the desired setting. The alphabetic settings and the linear markings are accurately calibrated and are precision repeatable from unit to unit.

The RESET pot on all units leaves the factory set at RESET “B” which means the gauge will reset to “Full” if the voltage of a newly installed battery is above 2.09 VPC. MARCH 1996

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Electrical Turning the pot clockwise from “B” to “E” increases the voltage per cell required to reset the gauge.

Turning it counter-clockwise toward “A” decreases the voltage per cell required to reset the gauge.

Example: With the new generation batteries, particularly those of the high acid type, open circuit voltage can be a bit higher then in lower acid batteries. In such cases, to properly align the unit to the particular battery characteristics, simply adjust the RESET pot to a level above the “C” marking for reset to occur when the battery's voltage is above 2.12 VPC, the higher open circuit voltage.

Example: In those circumstances when shutdowns cannot be tolerated because of the negative effect on productivity and it is necessary to use a partially charged battery, the gauge reset level can be decreased from 2.09 VPC to as low as 2.00 VPC. Though the gauge initially reads “Full” once it resets, as the equipment is used it will quickly catch up with the battery and provide a correct reading of the actual state-of-charge of the partially charged battery.

Keep in mind that RESET adjustments must be made prior to connecting the battery to the equipment. RESET adjustments made after battery/ equipment connection have no effect. The RESET action is instantaneous. The gauge will reset or not within seconds. If reset does not occur and it is necessary to readjust the pot setting, first unplug the battery and equipment, wait at least 10 seconds, adjust pot to new setting and reconnect the battery.

The DISCHARGE pot on all units leaves the factory set at DISCHARGE “N”, which means the discharge profile is set for a final end point of 1.73 VPC, where lockout will occur. This profile has proven to be the most common.

Turning the pot clockwise from “N” to “P” decreases the depth of discharge and, in turn, the operating time of the equipment. Turning it counter-clockwise from “N” to “K” increases the depth of the discharge and, in turn, the operating time of the equipment.

Example: On occasion, equipment is required for work beyond its normally assigned work cycle and time does not permit changing of battery. In these cases, lift lockout can be delayed by increasing the 2.38

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Electrical depth of discharge from the standard 1.73 VPC (“N” setting) to as low as 1.56 VPC (beyond “K” setting).

Example: Equipment and battery are sized for the type of work they are used for. On occasion, equipment designated for heavy work might be used for light tasks. Lighter work means low-current drain which, in turn, means the recommended 80% depth of discharge lockout point will be at a higher voltage level. In these cases, to properly align the low-current work profile and the required higher lift lockout point, the DISCHARGE pot can be adjusted to the “O” (1.78 VPC) or the “P” (1.82 VPC) settings.

It is important to note that adjustments of the DISCHARGE pot can be made at any time during a work cycle prior to lift lockout. however, DISCHARGE pot adjustments made late in a work cycle have little or no effect in delaying lift lockout in that particular work cycle. Once lift lockout does occur, the gauge must be reset before DISCHARGE pot adjustments can have an effect.

Table of Pot Settings and Associated Voltages Per Cell

DISCHARGE

RESET

P

1.82 VPC*

E

2.18 VPC

O

1.78

D

2.15

N factory set

1.73

C

2.12

M

1.68

B factory set

2.09

L

1.63

A

2.06

K

1.57

BEYOND K

1.56

BEYOND A ------------

2.00 ------------

*The DISCHARGE voltage of the unit is not an instantaneous voltage, nor a measure of the open circuit voltage at the time of lift lockout.

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2.39

Electrical Controller adjustments - 12 volt Plug Current Adjust CW=Higher Plugging Current

Location of the adjustment potentiometer on the 12 volt controller.

To make the adjustments: 1. Remove the socket head screw (1/8” Allen) for the adjustment you want to make.

2. Adjust the small internal potentiometer with a small trim pot adjustment tool. These are 270 degree turn potentiometer.

Acceleration Adjust CW=Faster Acceleration

NOTE: If the proper tool is not used to adjust these potentiometers, it is possible to damage the printed circuit board causing the controller fail.

3. Replace the socket head screw and nylon seal washer. Tighten to 8 inch/pounds.

4. Both of these adjustments can be made to suit the operator.

Higher plugging current will mean a shorter stopping distance when plugging. This distance should not be shorter then 10 feet.

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Electrical Controller adjustments - 24 volt Location of the adjustment potentiometer on the 24 volt controller.

To make the adjustments: 1. Remove the rubber plug strip from the controller.

2. Adjust the small internal potentiometer with a small insulated screwdriver. These are 270° (less then 1 turn) potentiometer.

3. Replace the plug strip when adjustments are complete.

4. Potentiometer #1 will adjust the creep speed.

Clockwise adjustment, higher numbers, will give a faster creep speed.

Potentiometer #2 will adjust the Controlled Acceleration. This is the amount of time the control takes to accelerate to 96% “on time” upon start up with full accelerator pot movement.

Clockwise adjustment, higher numbers, will give a shorter time and faster acceleration.

Potentiometer #3 will adjust the current limit at stall speed. This is preset at the factory and should not be adjusted. Contact the BT PrimeMover service department if adjustment is necessary.

Potentiometer #4 will adjust the minimum field current at top speed. This is preset at the factory and must not be adjusted. Contact the BT Prime-Mover service department if you feel that adjustment is necessary.

Potentiometer #5 will adjust the field and armature current ratio. This is preset at the factory and must not be adjusted. Contact the BT Prime-Mover service department if you feel that adjustment is necessary.

(1) Creep

(2) C/A

(3) C/L

(4) IFmin

(5) Field Ratio

PMX Potentiometer Settings MARCH 1996

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2.41

Electrical 2.5Troubleshooting Troubleshooting can be broken down into individual circuits. By knowing the exact symptoms of the truck operation many hours of troubleshooting time can be saved. If the proper contactor operates for the chosen direction and speed then the problem can be found in the power circuit of that function. If a particular contactor does not operate when a function is chosen then the problem can generally be found in the control circuit of that function.

Only the travel functions are controlled by the transistor controllers. Lift, lower, and horn functions operate separately.

To use this troubleshooting guide locate the failure symptom in the index on the starting on page 2.44 then go to the expanded outline and follow the testing procedures described.

Voltage tests are made with the negative lead of the volt meter connected to battery negative. If the negative lead is connected to a negative terminal on the electrical panel you must first verify the negative connection to the battery by touching the positive meter lead to the positive battery post. The battery voltage must be at least 25.2 volts for a 24 volt system. If the battery voltage is below 22 volts (no load) then the controller may not operate properly.

The battery voltage must be at least 12.6 volts for a 12 volt system. If the battery voltage is below 11 volts (no load) then the controller may not operate properly. You will then have to charge the battery before starting the troubleshooting procedures.

When testing voltage, the “POSITIVE SIDE” of any component refers to the terminal on that component that is closest electrically to the battery positive terminal. The “NEGATIVE SIDE” of any component refers to the terminal on that component that is farthest electrically from the battery positive terminal. It is possible, and in many cases desirable, to measure battery voltage on the negative side of a component.

“Forward” direction refers to travel in the direction of the control handle with the forks trailing. “Reverse” direction refers to travel with the forks leading. The control handle operating position is between 20 degrees below fully raised and 10 degrees above 2.42

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Electrical fully lowered. When the control handle is fully raised or fully lowered the brakes are applied and the brake interlock switch cuts off all power to the travel control circuits. The line contactor will also open. On a 12 volt truck the line contactor will open immediately. On a 24 volt truck the line contactor will open after a 15 second delay.

After the final test is completed the truck should be repaired and operating properly. If it is not, then you must verify your test results and possibly reevaluate the failure symptoms. If you still have not repaired the truck then you should call your local BT Prime-Mover dealer for assistance. When you call, the following information is required: Truck model and serial number, service meter hours, actual battery voltage at open circuit and at hydraulic operation under full load, the precise operating symptoms, and the exact results of the testing you have done. Authorized BT Prime-Mover dealers may call the factory directly if necessary.

The first steps of any troubleshooting procedure are to: 1. Inspect the truck for physical damage or mechanical malfunction. Contactors must be free to move and the tips must not be welded or burnt.

2. Check for ground faults from the electrical system to the frame with on ohmmeter. A minimum of 20,000 ohms resistance from the frame to any and all wiring is acceptable.

3. Check that the battery is fully charged and connected.

4. Operate the truck in all modes to determine the exact symptoms. Do not forget that these systems are equipped with safety circuits that prevent operation in the event of improper operating procedures.

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2.43

Electrical TROUBLESHOOTING CHART INDEX 12 volt trucks 2.5.1

Dead truck, nothing operates. No travel, no lift, no lower, no horn.

2.5.2

No travel, line contactor does not close. Lift, lower, and horn function okay.

2.5.3

No reverse travel (forks leading); reverse contactor will not close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower, and horn functions work okay.

2.5.4

No forward travel (forks trailing); forward contactor will not close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower, and horn functions work okay.

2.5.5

No reverse travel (forks leading); reverse contactor does close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower, and horn functions work okay.

2.5.6

No forward travel (forks trailing); forward contactor does close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower, and horn functions work okay.

2.5.7

Truck travel speed does not respond to controls properly. Contactors close for chosen direction but truck does not have full speed control.

2.5.8

Truck does not travel in reverse (fork direction) when red reverser switch is depressed.

2.5.9

Lift function does not operate.

2.5.10 Lift motor does not turn off at full height.

2.5.11 Lowering function does not operate.

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MARCH 1996

Electrical TROUBLESHOOTING CHART INDEX 24 volt trucks 2.5.12 Dead truck, nothing operates. No travel, no lift, no lower, no horn.

2.5.13 No travel, line contactor does not close. Lift, lower, and horn function okay.

2.5.14 No reverse travel (forks leading). Line contactor closes when control handle is pulled down to operating position. Forward travel and the lift, lower, and horn functions work okay.

2.5.15 No forward travel (forks trailing). Line contactor closes when control handle is pulled down to operating position. Reverse travel and the lift, lower, and horn functions work okay.

2.5.16 Truck travel speed does not respond to controls properly. Speed control is sluggish or erratic.

2.5.17 Improper operation of emergency reverse circuit; truck will not move in fork direction when emergency reverse button is pressed.

2.5.18 Lift function does not operate.

2.5.19 Lift motor does not turn off at full lift height.

2.5.20 Lowering function does not operate.

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2.45

Electrical TROUBLESHOOTING CHARTS The following troubleshooting charts describe a course of testing and repair for each problem listed. If the given test is NOT successful perform the repair listed with the test. If the given test IS successful move on directly to the next test or follow the special instructions given.

2.5.1

Dead truck, nothing operates. No travel, no lift, no lower, no horn.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Test for voltage at: A. Positive side of 110 amp circuit breaker.

Repair open power cable between battery positive terminal and 110 amp circuit breaker.

B. Positive side of 10 amp control fuse, wire #28.

Repair open wire #28 between 110 amp circuit breaker and 10 amp control fuse.

C. Negative side of 10 amp control fuse, wire #26.

Replace 10 amp control fuse.

D. Positive side of emergency disconnect push-button switch, wire #26.

Repair open wire #26 between 10 amp control fuse and emergency disconnect push-button switch.

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Electrical E. Negative side of emergency disconnect push-button switch, wire #27.

Replace emergency button switch.

disconnect

push-

F. Positive side of key switch, wire #27.

Repair broken wire #27 between emergency disconnect push-button switch and key switch.

G. Positive side of key switch, wire #6.

Replace key switch.

H. If truck is not functioning re-evaluate symptoms and troubleshoot individual functions.

2.5.2

No travel, line contactor does not close. Lift, lower, and horn function okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Test for battery voltage at: A. Positive side of brake interlock switch, wire #6.

Repair wire #6 between key switch and brake interlock switch.

B. Negative side of brake interlock switch, wire #7.

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2.47

Electrical Adjust or replace brake interlock switch.

C.Positive side of line contactor coil, wire #7.

Repair open wire #7 between brake interlock switch and line contactor coil.

D. Negative side of line contactor coil, wire #13.

Special instructions: If battery voltage is found here then repair open wire #13 to battery negative.

If no battery voltage is found here then replace line contactor coil.

2.5.3

No reverse travel (forks leading); reverse contactor will not close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower, and horn functions work okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Travel controls operated to travel in the reverse direction (forks leading).

Test for battery voltage at: A. Positive side of reverse direction control switch, wire #7.

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Electrical Repair open wire #7 between brake interlock switch and reverse direction control switch.

B. Negative side of reverse direction control switch, wire #3.

Adjust or replace reverse direction control switch.

C. Positive side of reverse contactor coil, wire #3.

Repair open wire #3 between reverse direction control switch and reverse contactor coil.

D. Negative side of reverse contactor coil, wire #13.

Special Instructions: If battery voltage is found here then repair open wire #13 to battery negative.

If no battery voltage is found here then replace reverse contactor coil.

See also troubleshooting chart 2.5.8.

2.5.4

No forward travel (forks trailing); forward contactor will not close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower and horn functions work okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake

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2.49

Electrical interlock switch closed.

Travel controls operated to travel in the forward direction (forks trailing).

Test for battery voltage at: A. Positive side of forward direction control switch, wire #7.

Repair open wire #7 between brake interlock switch and forward direction control switch.

B. Negative side of forward direction control switch, wire #2.

Adjust or replace forward direction control switch.

C. Wire #2 on common terminal on upper contact of relay #2.

Repair open wire #2 between forward direction control switch and relay #2.

D. Wire #32 on normally closed terminal on upper contact of relay #2.

Test for voltage on wire #18 on normally open terminal on upper contact of relay #2.

If no voltage then replace relay #2. If positive battery voltage is measured then go to troubleshooting chart #2.5.5.

E. Positive side of forward contactor coil, wire #32.

Repair open wire #32 between forward direction control switch and forward contactor coil.

F. Negative side of forward contactor coil, wire #13.

Special Instructions: If battery voltage is found here then repair open wire #13 to battery negative.

If no battery voltage is found here then 2.50

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Electrical replace forward contactor coil.

See also troubleshooting chart 2.5.8.

2.5.5

No reverse travel (forks leading); reverse contactor does close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower, and horn functions work okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to the operating position with brakes released and brake interlock switch closed.

Travel controls operated to travel in the reverse (forks leading) direction with reverse contactor closed.

Test for battery voltage at: A. Wire #7 terminal on transistor controller.

Repair open wire #7 between brake interlock switch and transistor controller.

B. Positive side of 110 amp circuit breaker.

Repair open power cable between battery positive terminal and 110 amp circuit breaker.

C. Negative side of 110 amp circuit breaker.

Replace 110 amp circuit breaker.

D. Positive side of line contactor tips.

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2.51

Electrical Repair open power cable between 110 amp circuit breaker and line contactor.

E. Negative side of line contactor tips.

Repair or replace line contactor.

F. B+ terminal on transistor controller.

Repair open power cable between line contactor and transistor controller.

G. A1 terminal on drive motor.

Repair open power cable between transistor controller B+ terminal and drive motor A1 terminal.

H. A2 terminal on drive motor.

Repair drive motor.

I. S2 terminal on drive motor.

Repair open power circuit between drive motor A2 terminal and drive motor S2 terminal.

NOTE: This includes the normally open (N.O.) reverse contactor tips.

J. S1 terminal on drive motor.

Repair drive motor.

K. M- terminal on transistor controller.

Repair open power circuit between drive motor S1 terminal and M- terminal on transistor controller.

NOTE: This includes the normally closed (N.C.) forward contactor tips.

L. B- terminal on transistor controller.

Special Instructions: If battery voltage is found here then repair open power cable to battery negative.

If no battery voltage is found here then it is 2.52

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MARCH 1996

Electrical possible that the transistor controller has failed. Before replacing the transistor controller perform the tests for the accelerator potentiometer listed in chart 2.5.8.

2.5.6

No forward travel (forks trailing); forward contactor does close when travel controls are operated. Line contactor closes when control handle is pulled down to operating position and the lift, lower, and horn functions work okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to the operating position with brakes released and brake interlock switch closed.

Travel controls operated to travel in the forward (forks trailing) direction with forward contactor closed.

Test for battery voltage at: A. Wire #7 terminal on transistor controller.

Repair open wire #7 between brake interlock switch and transistor controller.

B. Positive side of 110 amp circuit breaker.

Repair open power cable between battery positive terminal and 110 amp circuit breaker.

C. Negative side of 110 amp circuit breaker.

Replace 110 amp circuit breaker.

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2.53

Electrical D. Positive side of line contactor tips.

Repair open power cable between 110 amp circuit breaker and line contactor.

E. Negative side of line contactor tips.

Repair or replace line contactor.

F. B+ terminal on transistor controller.

Repair open power cable between line contactor and transistor controller.

G. A1 terminal on drive motor.

Repair open power cable between transistor controller B+ terminal and drive motor A1 terminal.

H. A2 terminal on drive motor.

Repair drive motor.

I. S1 terminal on drive motor.

Repair open power circuit between drive motor A2 terminal and drive motor S1 terminal.

NOTE: This includes the normally open (N.O.) forward contactor tips.

J. S2 terminal on drive motor.

Repair drive motor.

K. M- terminal on transistor controller.

Repair open power circuit between drive motor S2 terminal and M- terminal on transistor controller.

NOTE: This includes the normally closed (N.C.) reverse contactor tips.

L. B- terminal on transistor controller.

Special Instructions: If battery voltage is found here then repair open power cable to battery negative.

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MARCH 1996

Electrical If no battery voltage is found here then it is possible that the transistor controller has failed. Before replacing the transistor controller perform the tests for the accelerator potentiometer listed in chart 2.5.8.

2.5.7

Truck travel speed does not respond to controls properly. Contactors close for chosen direction but truck does not have full speed control.

NOTE: There are two series of tests for the accelerator potentiometer circuits. The first series will test the resistance through the potentiometer circuit and the second series will test the control voltages on the transistor controller.

Resistance testing Conditions for testing: Battery disconnected from truck.

Truck blocked to prevent it from rolling.

Wires #9 and #10 removed from transistor controller.

Test Procedure: Connect an ohmmeter with at least a 10K ohm scale to wires #9 and #10 that were removed from transistor controller. The purpose is to test the resistance through the accelerator potentiometer as the travel controls are operated through their full range in both directions. Operate travel controls slowly and smoothly to full speed in both directions: read ohmmeter.

Test Results: In neutral the resistance should be approximately 5000 ohms through the accelerator potentiometer circuit. As the controls are operated to high speed the resistance through the accelerator potentiometer circuit should drop smoothly to about zero (0) ohms.

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2.55

Electrical Recommended Action: If the test indicates an open circuit between wires #9 and #10 then repair the broken wire #9 or #10 or replace the accelerator potentiometer as necessary.

If the test indicates zero (0) ohms resistance between wires #9 and #10 repair the short circuit or replace the accelerator potentiometer as necessary.

If the test indicates improper potentiometer function in both directions then adjust or replace accelerator potentiometer. If the test indicates improper potentiometer function in only one direction then the problem is mechanical and can be found in the control linkage.

Voltage Testing Conditions for testing: Wires #9 and #10 transistor controller.

reconnected

to

Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Test Procedure: Connect a volt meter with at least a 20 volt DC scale to the terminals on the transistor controller with wires #9 and #10 connected.

The purpose is to test the voltage differential between wires #9 and #10 as the travel controls 2.56

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MARCH 1996

Electrical are operated through their full range in both directions. Operate travel controls slowly and smoothly to full speed in both directions: read volt meter.

Test Results: In neutral the voltage difference should be 3 to 4 volts DC. As the controls are operated to high speed the voltage should drop to close to zero (0) volts.

Recommended Action: If the test indicates proper accelerator voltage then replace the transistor controller.

NOTE: Some mechanical problems, such as brake adjustment, could cause the same symptoms. Be sure that this is not the case before replacing the transistor controller.

If the test indicates improper accelerator voltage then verify correct resistance tests before replacing transistor controller.

2.5.8 Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Red reverser switch depressed.

Drive motor and drive tire will spin at high speed during test. Do not allow any test leads, tools, clothing, or yourself to contact moving parts.

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2.57

Electrical Test for battery voltage at: A. Positive side of emergency reverse switch, wire #6.

Repair open wire #6 between key switch and emergency reverse switch.

B. Negative side of emergency reverse switch, wire #11.

Replace emergency reverse switch.

C. Positive side of first diode, wire #11.

Repair open wire #11 between emergency reverse switch and first diode.

D. Negative side of first diode, wire #18.

Replace first diode E. Wire #11, position #7 relay #2 Repair open wire #11 between first diode and position #7 relay.

F. Wire #13, position #8 relay #2.

Battery volts -- Repair open wire #13 between position #8 relay #2 and battery negative.

If relay is not operating, replace relay.

If relay is operating, continue with test G. Additional conditions for testing for G and beyond: Wires #22 and #9 disconnected form PMC controller. These are the two individual control wires on the PMC controller that are not in the seven-pin plug-in connector.

Wire #2, position #5 and wire #32, position #1 disconnected from relay #2 Ohmmeter set up for continuity testing.

G. Test continuity with Ohmmeter connected to 2.58

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Electrical wire #9 that was removed from PMC controller and wire #22 that was removed from PMC controller.

No continuity -- Repair open circuit. This may be wire #9 or wire #22 or relay #2.

H. Test continuity with Ohmmeter connected to position #5 on relay #2 and position #1 on relay #2.

Continuity, yes -- Replace relay #2.

Test -- Reverser switch circuits.

Conditions for testing: Wires re-connected to relay #2 and to PMC controller.

Truck raised and blocked with drive tire off ground.

Battery charged and connected to truck Emergency disconnect push-button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

A. Wire #11 on anode of two (2) reverser diode.

NOTE: These are plug-in diodes in the wiring harness.

0 Volts -- Repair open wire #11 between negative side of reverser switch and reverser diodes anode.

B. Wire #18 on cathode side of first reverser diode.

0 Volts -- Replace first diode.

C. Wire #18, Pin #5, in seven-pin plug-in connector on PMC controller.

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2.59

Electrical 0 Volts -- Repair open wire #18 between cathode of first reverser diode and pin #5 in seven-pin plug-in connector on PMC controller.

D. Wire #3 on cathode side of second reverser diode.

0 Volts -- Replace second diode E. Positive side of reverse contactor coil.

0 Volts -- Repair open wire #3 between cathode of second reverser diode and positive side on reverse contactor coil.

F. Wire #3, pin #7, in seven-pin plug-in connector on PMC controller.

0 Volts -- Repair open wire between cathode of second reverser diode and pin #7 in seven-pin plug-in connector on PMC controller.

2.5.9

Lift function does not operate.

Conditions for testing: Truck blocked to prevent it from rolling.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Lift switch bar pushed to close lift switch.

Test for battery voltage at: A. Positive side of lift switch, wire #6.

Repair open wire #6 between key switch and lift switch.

B. Negative side of lift switch, wire #5.

Adjust or replace lift switch and bar assembly.

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MARCH 1996

Electrical C. Positive side of lift limit switch, wire #5.

Repair open wire #5 between lift switch and lift limit switch.

D. Negative side of lift limit switch, wire #17.

NOTE: If pallet forks are fully raised then the lift limit switch should be open to shut off the lift motor.

Adjust or replace lift limit switch.

E. Positive side of lift contactor coil, wire #17.

Repair open wire #17 between lift limit switch and lift contactor coil.

F. Negative side of lift contactor coil, wire #13 (Wire #43 if truck is equipped with Lift Interrupt System).

Special Instructions: If truck is NOT equipped with Lift Interrupt System follow step “a”. If truck IS equipped with Lift Interrupt System follow step “b”. (a) For trucks WITHOUT Lift Interrupt System.

If battery voltage is measured here then repair open wire #13 between lift contactor coil and battery negative.

If battery voltage is NOT measured here continue testing with test G. (b) For trucks WITH Lift Interrupt System.

Test for battery voltage at terminal 6 on back of BDI gauge, wire #43.

If battery voltage is NOT measured here then repair open wire #43 between lift contactor coil and BDI gauge.

If battery voltage IS measured here then continue to test (c). (c).Test for battery voltage at negative terminal on back of BDI gauge, wire #13.

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2.61

Electrical If battery voltage IS measured here repair open wire #13 between BDI gauge and battery negative. Also verify that battery voltage is sufficient for Lift Interrupt System to allow lift function to operate.

If battery voltage is NOT measured here replace BDI gauge which contains the Lift Interrupt System. (d) ALL testing to resume with test G. G. Positive side of 110 amp circuit breaker.

Repair open power cable between battery positive terminal and 110 amp circuit breaker.

H. Negative side of 110 amp circuit breaker.

Replace 110 amp circuit breaker.

I. Positive side of lift contactor tips.

Repair open power cable between 110 amp circuit breaker and lift contactor.

J. Negative side of lift contactor tips.

Replace lift contactor.

K. A1 terminal on lift motor.

Repair open power cable between lift contactor and lift motor.

L. S2 terminal on lift motor.

Special Instructions: If battery voltage IS measured here then repair open power cable between lift motor and battery negative.

If battery voltage is NOT measured here then repair lift motor.

2.5.10 Lift motor does not turn off at full lift height.

Adjust or replace lift limit switch.

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MARCH 1996

Electrical 2.5.11 Lowering function does not operate.

Conditions for testing: Truck blocked to prevent it from rolling.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Lowering switch bar pushed to close lowering switch.

Test for battery voltage at: A. Positive side of lowering switch, wire #6.

Repair open wire #6 between key switch and lowering switch.

B. Negative side of lowering switch, wire #4.

Adjust or replace lowering switch and bar assembly.

C. Positive side of lowering valve coil.

Repair open wire #4 between lowering switch and lowering valve coil.

D. Negative side of lowering valve coil, wire #13.

Special Instructions: If battery voltage IS measured here then repair open wire #13 between lowering valve coil and battery negative.

If battery voltage is NOT measured here then check operation of lowering valve coil by holding a screwdriver next to coil. If screwdriver is magnetically attracted to coil the problem is likely hydraulic contamination preventing valve from operating. If screwdriver is not magnetically attracted to coil then problem is likely a failed lowering valve coil. Replace valve and/or coil as necessary.

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2.63

Electrical TROUBLESHOOTING CHARTS 24 volt trucks The following troubleshooting charts describe a course of testing and repair for each problem listed. If the given test is NOT successful perform the repair listed with the test. If the given test IS successful move on directly to the next test or follow the special instructions given.

2.5.12 Dead truck, nothing operates. No travel, no lift, no lower, no horn.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Test for battery voltage at: A. Positive side of 110 amp circuit breaker.

Repair open power cable between battery positive terminal and 110 amp circuit breaker.

B. Positive side of 10 amp control fuse, wire #28.

Repair open wire #28 between 110 amp circuit breaker and 10 amp control fuse.

C. Negative side of 10 amp control fuse, wire #26.

Replace 10 amp control fuse.

D. Positive side of emergency disconnect push button switch, wire #26.

Repair open wire #26 between 10 amp 2.64

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Electrical control fuse and emergency disconnect push button.

E. Negative side of emergency disconnect push button switch, wire #27.

Replace emergency button switch.

disconnect

push

F. Positive side of key switch terminal #1, wire #27.

Repair broken wire #27 between emergency disconnect push button switch and key switch.

G. Negative side of key switch terminal #3, wire #6.

Replace key switch.

H. If truck is not functioning re-evaluate symptoms and troubleshoot individual functions.

2.5.13 No travel; line contactor does not close. Lift, lower, and horn functions work okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Test for battery voltage at: A. Plug Z-1, wire #27 on transistor controller.

Repair open wire #27 between emergency MARCH 1996

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2.65

Electrical disconnect push button transistor controller.

switch

and

B. Positive side of brake interlock switch, wire #6.

Repair open wire #6 between key switch and brake interlock switch.

C. Negative side of brake interlock switch, wire #7.

Adjust or replace brake interlock switch.

D. Plug Z-2; wire #7 on transistor controller.

Repair open wire #7 between brake interlock switch and transistor controller.

E. Positive side of emergency reverse switch, wire #6.

Repair open wire #6 between key switch and emergency reverse switch.

F. Negative side of emergency reverse switch, wire #11.

Adjust or replace switch.

emergency

reverse

G. Plug Z-8; wire #11 on transistor controller.

Repair open wire #11 between emergency reverse switch and transistor controller.

H. Battery positive “P” terminal, wire #29 on transistor controller.

Replace transistor controller.

I. Positive side of key switch, terminal 5, wire #29.

Repair open wire #29 between transistor controller and key switch.

J. Negative side of key switch, terminal 7, wire #33.

Replace key switch.

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MARCH 1996

Electrical K. Positive side of line contactor coil, wire #33.

Repair open wire #33 between key switch and line contactor coil.

L. Negative side of line contactor coil, wire #24.

Replace line contactor.

M. Plug PZ-4, wire #24 on transistor controller.

Repair open wire #24 between contactor and transistor controller.

line

N. SPECIAL INSTRUCTIONS: Test voltage at plug PZ-9, wire #9, on transistor controller. This voltage should be between 3 and 4 volts.

If voltage is below 3 volts then repair the accelerator potentiometer circuit. This may mean adjusting or replacing the accelerator potentiometer or repairing a short circuit from wire #9 to battery negative.

O. SPECIAL INSTRUCTIONS: Test voltage at plug PZ-6, wire #2, on transistor controller.

If voltage is measured at this point then make repairs to eliminate the source of this voltage. This may include adjusting or replacing forward control switch or repairing a short circuit from wire #2 to battery positive.

P. SPECIAL INSTRUCTIONS: Test voltage at plug PZ-7, wire #3, on transistor controller.

If voltage is measured at this point then make repairs to eliminate the source of this voltage. This may include adjusting or replacing reverse control switch or repairing a short circuit from wire #3 to battery positive.

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2.67

Electrical Q. SPECIAL INSTRUCTIONS: Test voltage at negative terminal “N” on transistor controller.

If voltage is measured at this point then repair open power cable between terminal “N” on transistor controller and negative battery terminal.

If no voltage is measured at this point replace transistor controller.

2.5.14 No reverse travel (forks leading). Line contactor closes when control handle is pulled down to operating position. Forward travel and the lift, lower, and horn functions work okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Travel controls operated to travel in the reverse direction (forks leading).

Test for battery voltage at: A. Positive side of reverse direction control switch, wire #7.

Repair open wire #7 between brake interlock switch and reverse direction control switch.

B. Negative side of reverse direction control switch, wire #3.

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Electrical Adjust or replace reverse direction control switch.

C. Plug PZ-7, wire #3, on transistor controller.

Repair open wire #3 between reverse direction control switch and transistor controller.

D. Special Instructions: For this test only! Remove only the power cable from the “P” terminal on transistor controller. Reconnect wire #29 to “P” terminal.

Disconnect battery and discharge capacitor before removing or connecting any electrical wiring.

Discharge capacitor by connecting a 50 ohm resistor across “P” and “N” terminals on transistor controller for several seconds.

Test for battery voltage on power cable that was removed from “P” terminal on transistor controller.

If battery voltage is NOT measured here then verify line contactor operation and replace line contactor, or repair open power cable from line contactor.

If battery voltage IS measured here then reconnect power cable to “P” terminal on transistor controller and continue with test E. E. A1 terminal on transistor controller.

Replace transistor controller.

F. A1 terminal on drive motor.

Repair open A1 cable between transistor controller and drive motor.

G. A2 terminal on drive motor and on transistor controller.

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2.69

Electrical Special Instructions: The voltage measured at all A2 designated points should vary from battery voltage in neutral to near zero (0) volts at full accelerator.

If the voltage remains at or near zero (0) volts repair the drive motor or A2 cable as necessary.

If the voltage remains at or near battery volts complete the tests in the chart as well as chart 2.5.19 before replacing transistor controller.

H. Special Instructions: Measure the voltage between S1 and S2 terminals on the transistor controller as the controls are operated from neutral to high speed in both directions.

This voltage should vary according to the accelerator position, the actual drive motor speed, and the load on the motor.

If the voltage dos not vary, or there is no voltage measured here, replace the transistor controller.

If the voltage varies accordingly then test and verify S1 and S2 cables and drive motor continuity.

2.5.15 No forward travel (forks trailing). Line contactor closes when control handle is pulled down to operating position. Reverse travel and the lift, lower, and horn functions work okay.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

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MARCH 1996

Electrical Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Travel controls operated to travel in the forward direction (forks trailing).

Test for battery voltage at: A. Positive side of forward direction control switch, wire #7.

Repair open wire #7 between brake interlock switch and forward direction control switch.

B. Negative side of forward direction control switch, wire #2.

Adjust or replace forward direction control switch.

C. Plug PZ-6, wire #2, on transistor controller.

Repair open wire #2 between forward direction control switch and transistor controller.

D. Special Instructions: For this test only! Remove only the power cable from the “P” terminal on transistor controller. Reconnect wire #29 to “P” terminal.

Disconnect battery and discharge capacitor before removing or connecting any electrical wiring.

Discharge capacitor by connecting a 50 ohm resistor across “P” and “N” terminals on transistor controller for several seconds.

Test for battery voltage on power cable that was removed from “P” terminal on transistor controller.

If battery voltage is NOT measured here MARCH 1996

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2.71

Electrical then verify line contactor operation and replace line contactor or repair open power cable from line contactor.

If battery voltage IS measured here then reconnect power cable to “P” terminal on transistor controller and continue with test E. E. A1 terminal on transistor controller.

Replace transistor controller.

F. A1 terminal on drive motor.

Repair open A1 cable between transistor controller and drive motor.

G. A2 terminal on drive motor and on transistor controller.

Special Instructions: The voltage measured at all A2 designated points should vary from battery voltage in neutral to near zero (0) volts at full accelerator.

If the voltage remains at or near zero (0) volts repair the drive motor or A2 cable as necessary.

If the voltage remains at or near battery volts complete the tests in the chart as well as chart 2.5.19 before replacing transistor controller.

H. Special Instructions: Measure the voltage between S1 and S2 terminals on the transistor controller as the controls are operated from neutral to high speed in both directions.

This voltage should vary according to the accelerator position, the actual drive motor speed, and the load on the motor. The polarity in forward will be opposite that of reverse.

If the voltage does not vary, or there is no 2.72

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MARCH 1996

Electrical voltage measured transistor controller.

here,

replace

the

If the voltage varies accordingly then test and verify S1 and S2 cables and drive motor continuity.

2.5.16 Truck travel speed does not respond to controls properly. Speed control is sluggish or erratic.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

QMX ONLY -- Rabbit switch pushed to close high speed switch Travel controls to be operated from neutral to full speed in both directions as tests are made.

A. Test voltage at plug PZ-9, wire #9, on transistor controller.

This voltage should start out between 3 and 4 volts in neutral and decrease smoothly to zero (0) volts at high speed in both directions.

QMX ONLY -- With high speed switch open the voltage should decrease smoothly to .7 volts in both direction.

If voltage does not change repair open wire #9 or #13 connected to accelerator potentiometer.

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2.73

Electrical QMX ONLY -- If voltage does not change repair open: (1)

Wire #9 between potentiometer and walk resistor.

(2)

Wire #19 between walk resistor and controller.

(3)

Wire #13 between potentiometer and negative.

If voltage changes but not smoothly or not below 1/2 volt then adjust or replace accelerator potentiometer.

QMX ONLY -- If voltage does not drop below .7 volt test high speed switch.

B. Transistor controller may be in thermal cutback. Allow controller to cool and retest.

C. Replace transistor controller.

2.5.17 Improper operation of emergency reverse circuit; truck will not move in fork direction when emergency reverse button is pressed.

Conditions for testing: Truck raised and blocked with drive tire off ground.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Control handle pulled down to operating position with brakes released and brake interlock switch closed.

Red, emergency reverse button on end of control handle pressed.

Test for voltage at: A. Plug PZ-8, wire #11 on transistor controller.

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MARCH 1996

Electrical Special Instructions: If battery voltage is measured at this point then replace or adjust emergency reverse switch or, eliminate short circuit from battery positive to wire #11.

2.5.18 Lift function does not operate.

Conditions for testing: Truck blocked to prevent it from rolling.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

Key switch turned “on”.

Lift switch bar pushed to close lift switch.

Test for battery voltage at: A. Positive side of lift switch, wire #6.

Repair open wire #6 between key switch and lift switch.

B. Negative side of lift switch, wire #5.

Adjust or replace lift switch and bar assembly.

C. Positive side of lift limit switch, wire #5.

Repair open wire #5 between lift switch and lift limit switch.

D. Negative side of lift limit switch, wire #17.

NOTE: If pallet forks are fully raised then the lift limit switch should be open to shut off the lift motor.

Adjust or replace lift limit switch.

E. Positive side of lift contactor coil, wire #17.

Repair open wire #17 between lift limit MARCH 1996

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2.75

Electrical switch and lift contactor coil.

F. Negative side of lift contactor coil, wire #13 (Wire #43 if truck is equipped with Lift Interrupt System).

Special Instructions: If truck is NOT equipped with Lift Interrupt System follow step “a”. If truck IS equipped with Lift Interrupt System follow step “b”. (a)

For trucks WITHOUT Lift Interrupt System.

If battery voltage is measured here then repair open wire #13 between lift contactor coil and battery negative.

If battery voltage is NOT measured here continue testing with test G.

(b)

For trucks WITH Lift Interrupt System.

Test for battery voltage at terminal #6 on back of BDI gauge, wire #43.

If battery voltage is NOT measured here then repair open wire #43 between lift contactor coil and BDI gauge.

If battery voltage IS measured here then continue to test (c).

(c). Test for battery voltage at negative terminal on back of BDI gauge, wire #13.

If battery voltage IS measured here repair open wire #13 between BDI gauge and battery negative. Also verify that battery voltage is sufficient for Lift Interrupt System to allow lift function to operate.

If battery voltage is NOT measured here replace BDI gauge which contains the Lift Interrupt System. (d) 2.76

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ALL testing to resume with test G. MARCH 1996

Electrical G. Positive side of 110 amp circuit breaker.

Repair open power cable between battery positive terminal and 110 amp circuit breaker.

H. Negative side of 110 amp circuit breaker.

Replace 110 amp circuit breaker.

I. Positive side of lift contactor tips.

Repair open power cable between 110 amp circuit breaker and lift contactor.

J. Negative side of lift contactor tips.

Replace lift contactor.

K. A1 terminal on lift motor.

Repair open power cable between lift contactor and lift motor.

L. S2 terminal on lift motor.

Special Instructions: If battery voltage IS measured here then repair open power cable between lift motor and battery negative.

If battery voltage is NOT measured here then repair lift motor.

2.5.19 Lift motor does not turn off at full lift height.

Adjust or replace lift limit switch.

2.5.20 Lowering function does not operate.

Conditions for testing: Truck blocked to prevent it from rolling.

Battery fully charged and connected to truck.

Emergency disconnect push button switch pulled out to the “run” position.

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2.77

Electrical Key switch turned “on”.

Lowering switch bar pushed to close lowering switch.

Test for battery voltage at: A. Positive side of lowering switch, wire #6.

Repair open wire #6 between key switch and lowering switch.

B. Negative side of lowering switch, wire #4.

Adjust or replace lowering switch and bar assembly.

C. Positive side of lowering valve coil.

Repair open wire #4 between lowering switch and lowering valve coil.

D. Negative side of lowering valve coil, wire #13.

Special Instructions: If battery voltage IS measured here then repair open wire #13 between lowering valve coil and battery negative.

If battery voltage is NOT measured here then check operation of lowering valve coil by holding a screwdriver next to coil. If screwdriver is magnetically attracted to coil the problem is likely hydraulic contamination preventing valve from operating. If screwdriver is not magnetically attracted to coil then problem is likely a failed lowering valve coil. Replace valve and/or coil as necessary.

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MARCH 1996

BATTERY PACK

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2.79

Electrical BATTERY PACK CHARGER DIAGRAM, SWING OUT

2.80

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PMX ONLY

MARCH 1996

Electrical BATTERY PACK CHARGER DIAGRAM, NDC BATTERY PACK

MARCH 1996

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2.81

Electrical BATTERY PACK CABLE ASSEMBLY, SWING OUT

PMX ONLY

12 VOLT

12 VOLT CABLE SYSTEM

24 VOLT

24 VOLT CABLE SYSTEM 2.82

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MARCH 1996

Electrical TROUBLESHOOTING THE CHARGER USED IN THE PMX BATTERY PACK This charger incorporates a very simple and reliable design which makes troubleshooting relatively easy. The repair procedure involves testing the output of the charger and then testing individual components. The test procedures follow a logical sequence of electrical flow through the circuit. Only standard hand tools and an AC/DC volt/ohm meter are required. A battery hydrometer is recommended.

Before checking charger disconnect AC power supply, unplug batteries, and discharge capacitor with an insulated screwdriver. All tests should be made with extreme caution when a test calls for the power to be “on” at the charger.

ELECTRICAL TESTING Equipment required: 1.Common hand tools.

2.AC/DC volt/ohm meter.

3.Battery connector with + to - loop (use on charger only).

4.Battery hydrometer.

INSTRUCTIONS: I. Check condition of batteries (check each cell).

A. Specific gravity-before and after charging.

Acceptable values: Dead battery - 1.180 Fully charged battery - 1.280 Any cell that is different by more then 20 points indicates a suspect battery.

B. Volts per cell, open circuit - before and after charging.

Acceptable values: Dead battery - 1.9 v/cell MARCH 1996

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2.83

Electrical Fully charged - 2.2 v/cell C. Charging rate - DC amps - at start and finish of charge cycle. *See chart I on page 2.88 D. Charging rate at battery - DC volts - at start and finish of cycle. *See chart II on page 2.88 II Visually inspect charger with all power disconnected.

A. Inspect AC power supply circuit breaker, wall, outlet, plug, cord.

B. Inspect charger for physical damage.

C. Inspect internally for loose or discolored connections and wires damaged due to overheating.

D. Inspect transformer discrepancies.

coils

for

obvious

E. Inspect the charger internal AC power fuse should be 10 amp rated.

NOTE: If the ac power fuse is blown it could indicate a shorted diode on the D.C. output circuit.

III. Testing the DC output circuit.

NOTE: If the ac power fuse blows or the D.C. 1 x circuit breaker trips check for reverse polarity of the battery connection.

A. Open circuit voltage test.

With the batteries disconnected and the charger turned on, the DC output voltage should be 1 1/2 times the rated DC voltage. *See chart III on page 2.88 B. Short circuit amperage test.

With the charger output battery connector short circuited (positive to negative jumper connector plugged into charger output connector), and the charger turned on, the DC 2.84

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MARCH 1996

Electrical output amps should be 80% of the normal DC amps. *See chart IV on page 2.88 1. With the charger in the “off” position connect AC power cord to appropriate AC power supply, connect with the + to - loop to the charger.

2. Turn on the battery charger and note the amp gauge reading. It should be as stated on the chart IV on page 2.88.

Leave the charger on for five minutes while watching the amp gauge. The amp gauge should remain steady. This verifies the condition of the circuit breaker and any loose connections.

3. Turn the charger off before disconnecting the jumper connector.

IV Testing components Before checking components disconnect AC power supply, unplug batteries, and discharge capacitor with an insulated screwdriver. All tests should be made with the charger disconnected unless otherwise stated.

Use extreme caution when a test calls for the power to be “on” at the charger.

A. Diodes 1. A quick test for shorted diodes may be made by connecting the leads of the ohmmeter to the charger battery connector terminals and testing for continuity in each direction. If the test shows open, the DC circuit breaker may be open. To bypass an open DC circuit breaker connect the test leads to the positive and negative lugs behind the circuit breaker, reverse the ohmmeter probes. A shorted diode will show continuity in both directions. You will have to test the diodes individually as shown above to determine which diode is faulty.

2. Disconnect the diode flexible leads to isolate the diodes from the circuit.

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2.85

Electrical 3. Use the ohmmeter to test the continuity of each diode in both directions. A shorted diode will show continuity in both directions and an open diode will show no continuity in either direction. A good diode will show continuity in only one direction.

4. Reconnect diode leads in charger.

B. Capacitor 1. Discharge capacitor.

2. Disconnect capacitor leads.

3. Set ohmmeter R x 10,000 scale and connect ohmmeter leads to terminals on capacitor. When needle (or display) quits moving, reverse leads.

On a good capacitor the needle will deflect to the right (low resistance) and then deflect back to the left (high resistance) each time the meter leads are reversed.

On a shorted capacitor the needle will deflect to the right (low resistance) and remain there.

On an open capacitor the needle will not deflect (stationary display).

4. Reconnect capacitor leads in the charger.

5. Set AC volt meter on a scale to read at least 500 volts AC. Connect meter leads to the capacitor terminals.

A shorted capacitor will indicate 0 volts AC. An open capacitor will indicate about 300 volts + or -20 volts AC. This is the same as the capacitor transformer winding voltage without a capacitor connected in circuit.

6. Turn on charger power.

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MARCH 1996

Electrical Before checking components disconnect AC power supply, unplug batteries and discharge capacitor with insulated screwdriver. All tests should be made with the charger disconnected unless otherwise stated.

Use extreme caution when a test calls for the power to be “on” at the charger.

C. Timer 1. The timer can be tested by rotating the timer knob clockwise to the one (1) hour mark. With the AC power connected the charger should turn off in one (1) hour.

V Overcharging problems Most complaints about charging problems can be remedied by following the above procedures; however, overcharging problems may not be the fault of the charger. Often times overcharging is caused by faulty batteries or poor connections. The following items should be checked to resolve problems of overcharging or failure of charging amps to taper down.

A. Charger and battery not properly matched.

Check the specifications on both batteries and the charger. This battery pack has been designed for a specific size and type of battery.

If another battery has been installed be certain that it is comparable to the original batteries.

Automotive type batteries will not function properly in this application.

B. Excessive battery temperatures suppressed battery voltage.

causing

Allow batteries to cool.

C. Defective battery or poor DC connection.

Check the battery voltage while the charger rate is controlled by the battery state of charge which will adjust the output to the proper level if MARCH 1996

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2.87

Electrical the battery is in good condition. If the voltage does not come up to finish rate this may indicate a bad cell within a battery or a marginal DC connection between the battery and the charger. Carefully inspect the connections for excessive heat. Test the battery cell voltages and specific gravity.

CHART I Acceptable values

Start

Finish @ 2.5 VPC

12 volt system

30 amps

10 amps or less

24 volt system

15 amps

.5 amps or less

CHART II Acceptable values

Start

Finish

2.13 v/cell

2.5 v/cell

12 volt system

12.8 volts

15.0 volts

24 volt system

25.6 volts

30.0 volts

CHART III System voltage

Short circuit output voltage

12 volts

18 volts

24 volts

36 volts

System voltage

Short circuit output voltage

12 volts

approx. 24 amps.

24 volts

approx 12. amps

CHART IV

2.88

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MARCH 1996

Electrical 2.6 Component Removal and Installation 2.6.1 Drive Motor Removal and Installation

Removal 1.

Disconnect the battery, block unit from moving and remove side cover over tire.

2.

Remove brake spring and disconnect brake linkage at clevis and remove entire lever from case.

3.

Disconnect brake interlock switch remove mounting bracket from case.

4.

Remove drive motor by disconnecting power cables and noting their proper position remove four (4) mounting bolts (motor will be loose when bolts are removed).

5.

Place drive motor assembly on a bench to continue disassembly.

6.

Remove locknut and pinion gear from motor armature shaft.

7.

Remove locknut and brake drum from motor armature shaft.

and

By lifting one brake shoe of the brake assembly at a time the mounting bolts can be removed without disassembling the brake assembly.

8.

Remove and discard old O ring replace with new O ring (coat new O ring with petroleum jelly (such as vaseline) before installation).

9.

To disassemble motor see the section in this manual covering the motor assembly.

Installation The drive motor can be reinstalled without removing the gear case cover by following these steps: 1.

Thoroughly clean all parts with solvent or other non-corrosive cleaning fluid. Air dry all parts.

The transmission should be assembled in a

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2.89

Electrical dirt-free area.

2.

Install brake assembly by lifting one brake shoe at a time and installing mounting bolts.

NOTE: Location of activating lever should be located as shown.

3.

Install brake drum on the armature shaft over the key.

4.

Install pinion gear on drive motor over the key and tighten locknut. Placing a wrench on both locknuts tighten nut to 30 ft./lbs.

5.

Install O ring on motor drive end.

NOTE: ALways make sure that O rings have been lubricated with petroleum jelly before installing.

6.

Slide drive motor in gear case and work it around until the motor lines up with intermediate gear.

7.

Install the four (4) motor mounting bolts and torque to 35 ft./lbs.

8.

Connect the power cables to their proper terminal.

9.

Install brake interlock connect wires.

switch

mounting

Wire number 6 goes to the common side of the switch and wire number 7 goes to the normally open terminal.

10. Install brake linkage and stretch spring across mounts.

11. Install the side cover over drive tire. Torque to 35 ft./lbs.

12. Remove blocks, connect battery and test operation of unit.

2.6.2 Drive Motor Brush Removal and Installation It is not necessary to remove the drive motor to replace the brushes.

1.

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Disconnect battery before beginning work.

MARCH 1996

Electrical 2.

Drive motor brushes are accessible by removing the side cover on left side of transmission over the motor and brake.

3.

Remove the shields around motor end cover to expose brushes.

4.

Remove screw holder brush lead.

5.

Lift spring off brush, remove brush from holder.

2.6.3 Pump and Motor Removal and Installation The hydraulic pump and motor assembly must be removed from the truck in order to separate the pump and motor. The lift frame must be fully lowered before removing pump.

1.

Lower lifting frame to release pressure in system.

2.

Disconnect battery, remove access covers, and key switch mounting bracket.

3.

Disconnect hydraulic hose and electrical cables. Disconnect solenoid control wiring.

4.

Unbolt pump and motor mounting bracket and remove assembly.

5.

Remove motor end cover for access to through bolts that hold motor to adapter.

6.

Remove through mounting bolts separate motor from pump adapter.

and

2.6.4 Pump Motor Brush Removal and Installation The brushes are accessible under the pump motor end cover and can be replaced without separating the motor and pump. Lift the brush spring and pull brush from holder, unscrew lead and remove brush.

Check that new brushes are properly seated during installation.

2.6.5 Switch, Control

Brake Interlock Switch The brake interlock switch is located under the drive motor cover. It is activated by the brake arm. Its MARCH 1996

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2.91

Electrical purpose is to shut OFF electrical power to the drive motor when the brake is applied (handle is fully up or down) by opening the control circuit. To adjust the interlock switch: 1.

Disconnect battery and block drive wheel off floor and remove drive motor cover.

2.

Leave the brake “ON” (handle up).

3.

Loosen the two (2) screws holding interlock switch on bracket and slide switch left, away from brake arm as far as possible.

4.

Slide switch to the right until switch clicks (snaps). Next move and additional 1/32 inch and tighten screws.

5.

Check that brake arm makes solid contact with the interlock switch lever.

6.

Check that switch clicks (snaps) near middle of the cam arm movement. Brake switch should operate within 10° of handle movement from the full up or full down position.

7.

Install drive motor cover and tighten torque to 35 ft./lbs.

8.

Remove blocks, connect battery and test operation of unit.

2.6.6 CONTACTOR TIPS

Contactor Tip Removal and Installation SHOCK HAZARD!!! Disconnect battery before doing any work on/or around contactor panel assembly.

Contactor Tip/Bar Replacement

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1.

Contactor tips are the only serviceable part of contactors. The bars should be replaced when tips have worn through the silver contact in any area.

2.

Disconnect buss bars from contactors.

3.

Remove screws holding contactor cover in place.

MARCH 1996

Electrical 4.

Remove cover, being careful not to drop springs.

5.

Install new bars and tips.

6.

Install cover with springs in correct place.

2.6.7 DIRECTION CONTROL SWITCHES The direction control switches are mounted in the control handle head. It is not necessary to remove the head to change the switches.

1.

Remove the six Torx® head screws around the outer edge of the switch cover plate on the control handle head. Do not remove the center screw. Lay cover to side.

2.

Remove two screws holding forward/reverse switch bracket to housing and remove bracket.

3.

Unplug switch wires and remove switches and bracket.

4.

The switches may now be replaced by unbolting them from the bracket.

5.

Reconnect switch wires and reinstall bracket in housing.

6.

Test switch operation and adjust bracket before installing switch cover plate.

2.6.8 POTENTIOMETER The accelerator potentiometer is accessible inside the control handle head by removing the switch plate. The accelerator potentiometer operates off a gear toothed shaft (rack) that is moved when the travel controls are twisted.

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1.

Disconnect the battery.

2

Remove the six (6) outside screws securing the raise/lower/horn switch plate to the control handle head. Do not remove the center screw on the switch plate. Remove the switch plate and lay it over to one side.

3.

Remove the control handle head.

4.

Push wire terminals for the potentiometer out 2.93

Electrical of the wiring harness connector plug.

5.

Remove the two (2) screw that secure the potentiometer bracket to the switch housing and remove the potentiometer, bracket, and gear as an assemble.

6.

Support the potentiometer side of the gear and using a small punch tap the potentiometer from the gear. (This is to prevent internal damage to the potentiometer.

7.

Remove the nut and washer securing the potentiometer to the bracket.

8.

Mount the new potentiometer into the bracket aligning the alignment pin on the potentiometer with the hole in the bracket.

Secure the potentiometer to the bracket with the star washer and nut.

9.

Push the gear onto the potentiometer until the gear is flush with the end of the potentiometer shaft.

10. Install the new wire terminals in same position of wiring harness connector plug as the wires removed in step #4.

11. Adjust the potentiometer per the service manual. (See section 2.4.2) 2.6.9 RAISE, LOWER AND HORN SWITCHES The raise, lower, and horn switches are mounted in the switch cover plate on the control handle head.

The switches are molded into the switch bar so the switch bar and switch will be replaced together as a single part. It will be necessary to remove the head to change the switches.

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1.

Remove the six Torx® head screws around the outer edge of the switch cover plate on the control handle head.

2.

Remove the control handle head (See 4.6.1).

3.

Remove center screw and nut holding switch bar retainer to cover plate. The switch bars and springs will now be free to come out.

4.

Push wire terminals for the failed switch out MARCH 1996

Electrical of the wiring harness connector plug.

5.

Install new switch wire terminals into plug.

6.

Position switch bars and springs into switch cover plate and reinstall switch bar retainer with one screw and nut.

7.

Reinstall control handle head.

8.

Reinstall switch cover plate.

2.6.10 Raise, Lower and Horn Switches (QMX Hand Rail) The raise, lower, and horn switches are mounted in the switch cover plate on the hand rail assembly.

The switches are molded into the switch bar so the switch bar and switch will be replaced together as a single part.

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1.

Remove the four Torx® head screws at the corners of the switch cover plate on the hand rail. (Do not remove the screws in the top and bottom center of the cover plate).

2.

Remove center screws and nuts holding switch bar retainer to cover plate. The switch bars and springs will now be free to come out.

3.

Disconnect wire terminals for the failed switch.

4.

Connect new switch wire terminals.

5.

Position switch bars and springs into switch cover plate and reinstall switch bar retainer with two screws and nuts.

6.

Reinstall switch cover plate.

2.95

Electrical 2.7 Component Repair 2.7.1 Drive Motor Disassembly 1.

Remove motor brushes.

2.

Remove four screws holding brush end bell to field housing.

3.

Separate end bell from field housing. The armature will come out with end bell.

Troubleshooting When a motor has trouble in operation, a reasonable decision has to be made as to the proper corrective course action. We have reviewed many troubleshooting guides, and have reduced them to a few which seem to be the most effective Symptom/Cause relationships.

Table 1 - Indications, causes and correction of unsatisfactory brush performance.

Table 2 - Primary sources of unsatisfactory brush performance.

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MARCH 1996

Electrical TABLE #1

Indications, Causes and Correction of Unsatisfactory Brush Performance Indications

Immediate Causes

Primary Faults

Sparking

Commutator surface condition Over-commutation Under-commutation Too rapid reversal of current Faulty machine adjustment Mechanical fault in machine Electrical fault in machine Bad load condition Poor equalized parallel operation Vibration Chattering of brushes Wrong brush grade Fluctuating contact drop

1-2-3-43-44-45-46-49-59-60 7-12-31-33 7-12-30-32 7-12-30-32 8-9-11 6-14-15-16-17-18-19-20-21-28-29 25-27-28-29-38-39-40-41-42

Etched or burned bands on brush face

Over commutation Under commutation Too rapid reversal of current

7-12-31-33 7-12-30-32 7-12-30-32

Pitting of Brush Face

Glowing Embedded copper

See “Glowing at brush face” See “Copper in brush face”

Rapid Brush Wear

Commutator surface condition

See specific surface fault in evidence. Also see 50.

See “Sparking”

Severe sparking Imperfect contact with commutator Wrong brush grade

7-13-23-34 51-52 See “Chattering or Noisy Brushes” 55-57-59 50

11-14-15-16-51-52 54-58

Glowing at Brush Face

Embedded copper Faulty machine adjustment Severe load condition Bad service condition Wrong brush grade

See “Copper in brush face” 7-12 38-39-41-42 46-47 57-61-62

Copper in Brush Face

Commutator surface condition Bad service condition Wrong brush grade

2-3 43-46-47-48-49 59-61

Flashover at Brushes

Machine condition Bad load condition Lack of attention

14-35 38-39-41-53 5-11

Chattering or Noisy

Commutator surface condition Looseness in machine Faulty machine adjust High friction Wrong brush grade

See specific surface in evidence 15-16-17 10-11 6-43-45-49-52-58-59 55-58-59

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2.97

Electrical TABLE # 1 (continued)

Indications Appearing at Commutator Surface Indications

Immediate Causes

Primary Faults

Brush Chipping or Breakage

Commutator surface condition Looseness in machine Vibration Chattering

See specific surface fault in evidence 15-16-17 52 See “Chattering or Noisy Brushes” 14

Sluggish brush movement

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Rough or Uneven Surface

1-2-3-4-17

Dull or Dirty Surface

5-44-60

Eccentric Surface

1-19-22-52

High Commutator Bar

Sparking

17

Low Commutator Bar Streaking or Threading of Surface

Sparking Copper or foreign material in brush face Glowing

2-25 43-44-45-46-49-59 2-3-46-47-48-61 See “Glowing at Brush Face”

Bar Etching or Burning

Sparking Flashover

2-3-7-12-30-31-32-33 5-11-14-35-38-39-41-53

Bar Marking at Pole Pitch Spacing

Sparking

25-37

Bar Marking at Slot Pitch Spacing

Sparking

7-12-30-57-60

Flat Spot

Sparking Flashover Lack of attention

19-23-25-41-53 5-11-14-35-38-39-41-53 1-5-11

Discoloration of Surface

High temperature Atmospheric condition Wrong brush grade

See “Heating at Commutator” 44-46 60

Raw Copper Surface

Embedded copper Bad service condition Wrong brush grade

See “Copper in Brush Face” 43-45-47-49 59-61

Rapid Commutator Wear with Blackened Surface

Burning Severe Sparking

2-3-11-14 See “Sparking”

Rapid Commutator Wear with Bright Surface Copper Dragging

Foreign material in brush face Wrong brush grade Brush vibration

43-45-47-49 61 39-52-58-59

MARCH 1996

Electrical TABLE # 1 (continued)

Indications Appearing as Heating Indications

Immediate Causes

Primary Faults

Heating in Windings

Severe load condition Unbalanced magnetic field Unbalanced armature currents Poorly equalized parallel operation Lack of ventilation

38-41-42-53 18-19-20-21-27-28-29

Severe load condition Severe sparking High friction Poor commutator surface Depreciation High contact resistance

38-41-42 7-8-9-12-20-33-45-57 10-11-36-43-45-49-58-59 See specific surface fault in evidence 6-24 56

Severe load condition Faulty machine adjustment Severe sparking Raw streaks on commutator surface Embedded copper Wrong brush grade

38-41-42 7-10-11-12-26 See “Sparking” See “Streaking or Threading of Surface” See “Copper in Brush Face” 57-58-59-61-62

Heating at Commutator

Heating at Brushes

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8-19-22-25-27-28-29-37 7-13-23-24

2.99

Electrical TABLE # 2

Primary Sources of Unsatisfactory Brush Performance Preparation and Care of Machine 1.

2.

3.

4.

5.

6.

Poor preparation of commutator surface High mica Feather-edge mica Bar edges not chamfered after undercutting Need for periodic cleaning Clogged ventilating ducts

Machine Adjustment 7.

8.

9.

10.

11.

12.

13.

Brushes in wrong position Unequal brush spacing Poor alignment of brush holders Incorrect brush angle Incorrect spring tension Interpoles improperly adjusted Series field improperly adjusted

Mechanical Fault in Machine 14.

15.

16.

17.

18.

19.

20.

21.

22.

23.

24.

Brushes tight in holders Brushes too loose in holders Brush holders loose at mounting Commutator loose Loose pole pieces or pole-face shoes Loose or worn bearings Unequal air gaps Unequal pole spacing Dynamic unbalance Variable angular velocity Commutator too small

Electrical Fault in Machine 25. Open or high resistance connection at commutator 26. Poor connection at shunt terminal 27. Short circuit in field or armature winding 28. Ground in field or armature winding 29. Reversed polarity on main pole or interpole

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MARCH 1996

Electrical Machine Design 30.

31.

32.

33.

34.

35.

36.

Commutating zone too narrow Commutating zone too wide Brushes too thin Brushes too thick Magnetic saturation of interpoles High bar-to-bar voltage High ratio of brush contact to commutator surface area 37. Insufficient cross connection of armature coils Load or Service Condition 38.

39.

40.

41.

42.

43.

44.

45.

46.

47.

48.

49.

50.

Overload Rapid change of load Reversing operation of non-interpole machine Plugging Dynamic braking Low average current density in brushes Contaminated atmosphere “Contact poisons” Oil on commutator or oil mist in air Abrasive dust in air Humidity too high Humidity too low Silicone contamination

Disturbing External Condition 51.

52.

53.

54.

55.

56.

57.

58.

59.

60.

61.

62.

MARCH 1996

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Loose or unstable foundation External source of vibration External short circuit or very heavy load surge “Commutation factor” too high “Commutation factor” too low Contact drop of brushes too high Contact drop of brushes too low Coefficient of friction too high Lack of film forming properties in brush Lack of polishing action in brush Brushes too abrasive Lack of carrying capacity

2.101

Electrical DISASSEMBLY 1. Remove the cover band from the commutator end of the motor (if equipped).

2. Use a brush hook to reach into the motor and lift the brush springs. Pull the brushes out of the brush holders. Either position the brushes outside the motor or remove the brush retaining screws and remove the brushes from the motor.

3. Scribe or center punch locating marks in the end head and the frame. Although locating marks are not always necessary because of locating pins in some motors, they can save a lot of time when the motor does not have locating pins.

4. Remove the commutator end head retaining screws. Almost all motors have a slip fit bearing at the commutator end, and the end head can be removed with very little trouble.

On motors that have a shaft extension on both ends of the armature, the attachment on the commutator end of the shaft must be removed before the end head can be separated from the motor.

5. Remove the drive end head retaining screws, if necessary. Some of the smaller pump motors retain the drive end head with the motor through bolts. Separate the armature and drive end head as an assembly from the frame and field coil assembly.

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MARCH 1996

Electrical 6. Separate the armature from the drive end head.

This operation is usually done by pressing the armature out of the drive end bearing. On some of the larger motors, the end head and bearing will have to be removed with a puller.

When a puller is used, protect the end of the armature shaft with a nut or a thick flat washer. If the shaft, coupling, or spline is damaged when removing the end head, the armature or the drive spline usually has to be replaced. Use caution and do not damage the armature.

Bearing Inner Race Snap ring

Press Ram

Pipe (same size as Inner Race)

7. Separate the bearing from the end head. On larger motors, the bearing is retained with a snap ring. Remove the snap ring. Then press the bearing out of the end head.

Commutator end head

Bearing

Armature shaft Pressing end head back on armature shaft

End head

Snap ring

8. The ventilation fans are cast aluminum. Once these fans have been pressed onto the armature, they must be heated to be removed without damage.

A puller is installed and a slight pressure exerted against the fan. Use a small propane torch to heat the area of the fan around the shaft. When the fan becomes loose on the shaft, as evidenced by the puller becoming loose, it should be removed as quickly as possible.

9. When the fan is reassembled on the shaft, make sure it is a tight fit. Use “Loctite Retaining Compound 40" or equivalent on the inside of the fan hub when reassembling fan.

Use “Loctite” on this area of shaft

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10. After the motor has been separated into all its major subassemblies, the components should be cleaned and inspected for wear or damage.

2.103

Electrical 2.7.2 CONTROLLERS No internal repairs can be made to the transistor controllers. Contact the parts department for exchange units.

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MARCH 1996

3.0 HYDRAULICS

MARCH 1996

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3.1

Hydraulics HYDRAULIC SCHEMATIC

LIFT CYLINDER

3200±50 PSI

HYDRAULIC PUMP

LIFT CONTROL SYSTEM SCHEMATIC 3.2

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MARCH 1996

Hydraulics HYDRAULIC SCHEMATIC SYMBOLS

COMPONENT ENCLOSURE

HYDRAULIC LINES JOINING

MOTOR (ELECTRIC)

HYDRAULIC PUMP

FILTER

RESERVOIR (VENTED) CYLINDER (SINGLE ACTING) CYLINDER (DOUBLE ACTING)

CHECK VALVE

HYDRAULIC LINES CROSSING

MARCH 1996

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3.3

Hydraulics Component Identification

Pump and Motor assembly

Lowering valve

3.4

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MARCH 1996

Hydraulics ITEM # NAME 1 2 3K 4K 5K 6 7 8 9 K

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Cylinder assembly Rod Ring Wiper Seal Tube Fitting, 90° Hose assembly Screw, socket flat head Kit, Seal (Contains Items Marked with “K”)

# FOR ASSY. 1 1 1 1 1 1 1 1 2 1

3.5

Hydraulics HYDRAULIC PUMP AND MOTOR ASSEMBLY

3.6

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MARCH 1996

Hydraulics ITEM # NAME 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

MARCH 1996

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Wire assembly Valve, NC solenoid Coil Valve, cartridge check O ring Wire assembly Motor, pump Coupler Pin, dowel Endhead O ring Seal, oil Cover, suction Washer Bolt, Torx® Magnet Screw, self tapping Reservoir assembly Elbow, 90° Breather Filter Tube, 4" long Screw, cap Pump assembly Bolt, Torx® Tube, 7" return Ball Spring Screw, relief adjuster Cap, relief O ring Plug O ring Cable assembly Plug, hole Connector, spade wire Screw, self tapping Contactor, pump Valve, flow control

# FOR ASSY. 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 4 1 1 1 1 1 2 1 2 2 1 1 1 1 1 2 1 1 1 1 2 1 1

3.7

Hydraulics 3.2 SYSTEM OPERATION 3.2.1

Raise pallet forks When the lift pump and motor are running fluid is drawn from the reservoir, through a pick up screen to the inlet of the gear pump. As the gear pump rotates, oil is forced out the pressure port and is blocked from returning to reservoir by the closed relief valve and lowering valve. The oil continues to flow to the base of the cylinder and pushes against the end of the cylinder rod to extend the rod from the cylinder barrel.

When the motor is shut off and the gear pump is not turning, the cylinder is held extended by the closed check valve and normally closed lowering valve.

3.2.2

Lower pallet forks Hydraulic fluid is retained in the hydraulic cylinder by the check valve and electrical solenoid lowering valve. When the solenoid is energized, an oil passage from the cylinder to the reservoir is opened. Due to the load on the lift cylinder, fluid is forced out of the cylinder and back to the reservoir while the cylinder is retracting. This process allows the machine to lower.

3.3

SPECIFICATIONS Hydraulic fluid type

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Standard truck

HYDO 32

Freezer application

Texaco 15

Hydraulic fluid capacity

1 quart

System relief pressure

2600 psi

MARCH 1996

Hydraulics 3.4 MAINTENANCE AND ADJUSTMENTS 3.4.1

Maintenance The hydraulic fluid level must be checked periodically; see the Planned Maintenance Schedule. If the reservoir regularly requires the addition of oil to maintain the proper level then a leak is indicated and must be repaired. When scheduled, the reservoir should be removed and drained for cleaning. When the system is refilled, or if the truck seems to not lift a full load, then the pressure relief setting should be checked and adjusted. During normal operation the pressure relief setting will not change. As the pump wear with age some loss of pressure and volume will be experienced. When this loss becomes severe the pump should be replaced.

3.4.2

Adjustments The only adjustment is the pressure relief setting. This adjustment is made by removing the screw cap on the pressure relief valve and turning the screw to make the adjustment. See page 3.4. Turning the screw in clockwise will increase the pressure relief setting.

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3.9

Hydraulics 3.5

TROUBLESHOOTING NOTE: Proper care and cleanliness should be observed in servicing so as to insure the oil does not become contaminated with dirt or other foreign material which can be drawn in the pump so as to stick or score pump which will cause failure of the pump assembly.

If hydraulic pump assembly does not operate properly a few preliminary checks should be made: 1. Proper oil level 2. All electrical connections tight 3. Battery fully charged After the preliminary check is accomplished, install a 0-3000 PSI pressure gauge in the pressure line near the 3/8” NPTF outlet port in the adapter. The installation of the pressure gauge is required to insure proper observation of what is occurring in the unit during trouble shooting. Start the pump and raise the cylinder to its upper limit stops to develop maximum pressure of the unit, which will normally be passing all flow over the relief valve. The pressure gauge should be reading the set pressure of the relief valve. Remove pressure on the system by actuating the solenoid operated release valve.

The normal troubles that may occur with the pump assembly have been grouped under three headings: Failure to (A) Raise (B) Hold (C) Lower the load. One or more of the listed trouble sources may be causing improper operation. Refer to the proper heading (i.e. relief valve) for detailed instructions for disassembly, check and adjustment of parts to remedy the trouble.

A. If pump operates but will only develop low pressure or slow lift: 1. Relief

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valve

seat

scored,

foreign

MARCH 1996

Hydraulics particles under ball or relief valve out of adjustment (see relief valve).

2. Dirt in solenoid operated release (see solenoid operated release valve).

3. Pump worn - replace pump.

B. If pump develops pressure but will not hold: 1. Dirt in solenoid operated release (see solenoid operated release valve).

2. Relief valve seat scored, foreign particles under ball or relief valve out of adjustment (see relief valve).

C. If pump develops pressure but will not release load: 1. No electrical contact to solenoid operated release valve (see solenoid operated release valve).

2. Solenoid in solenoid operated release valve burned out.

3. Relief valve bottomed causing pressure to go beyond the unloading limit of the solenoid release valve (see relief valve).

RELIEF VALVE Remove hex cap on relief valve. If relief valve is causing the low pressure condition, the pressure can be increased by screwing in the adjusting screw, recycling the pump and noting pressure gauge reading. Be sure the final adjustment on the screw is at least 1/2 turn from bottoming position. If the trouble is not remedied by the relief valve adjustment, remove adjustment screw and spring and ball.

Valve seat should be clean and not scored.

Replace spring and ball in cavity. Insert 1/4” drive pin punch down through spring coils and hold ball against valve seat. Tap gently on drive pin punch with ball peen hammer to seat the ball. Reassemble the relief valve parts. Adjust relief valve and recycle the pump per above. Do not operate motor/pump at relief valve setting MARCH 1996

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3.11

Hydraulics any longer then is necessary (No longer then 10 seconds at any one period).

Removing Solenoid Operated Release Valve.

Clean surface around valve before starting to avoid foreign matter from falling into cavity.

Disconnect wires form terminals on coil, loosen and remove nut. Remove coil. Using wrench on flat surface, loosen and remove tube subassembly unit. Remove, inspect and clean or replace strainer as required.

Install Solenoid Operated Release Valve.

Clean and inspect valve cavity to be sure it is free of all foreign matter.

CAUTION DO NOT bend or apply pressure to

center stud or hold cartridge body any place but on flat sides of subassembly.

Be sure O ring and Teflon ring are in place.

Apply a small amount of clean grease to all three rings. Be sure strainer is in place. Hand screw sub-assembly in place and tighten to a maximum of 35 ft./lbs. for die cast metal.

Assemble coil on spool assembly and tighten nut to a maximum of 5 ft./lbs. Connect wires to terminals on coil.

3.6 Component Removal and Installation 3.6.1

Pump and Motor Removal and Installation The hydraulic pump and motor assembly must be removed from the truck in order to separate the pump and motor. The lift frame must be fully lowered before removing pump.

1. Lower lifting frame to release pressure in system.

2. Disconnect battery, remove access covers and key switch mounting bracket.

3. Disconnect

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hydraulic

hose

and

MARCH 1996

Hydraulics electrical cables. Disconnect solenoid control wiring.

4. Remove the two socket head screws securing the hydraulic pump and motor assembly to the battery side of the frame.

5. Remove pump and motor assembly.

3.6.2

Removing and Installing Reservoir and Pump It is necessary to remove the reservoir for access to the pump.

Removing Reservoir Drain reservoir of oil. Set unit in vertical position with reservoir end up. Remove four 1/4” screws holding on reservoir. Tap reservoir lightly to loosen. Wiggle the reservoir sideways while pulling up at the same time.

Removing Pump Remove pump inlet tube. Remove four (4) screws holding pump to adapter. Lift pump off.

Installing Pump Oil O ring lightly and install on pump pilot. Align splines on motor drive and pump shaft. Gently push pump pilot in adapter.

When pump is flush with adapter, pump and motor are connected. Replace four (4) screws, torque to 10-12 ft./lbs. Check strainer for clogging. Wash in suitable solvent, blow out with air hose from inside out. Insert inlet tube in pump.

Installing Reservoir 1. Examine the inside leading edge of reservoir for any burrs or nicks that may cut O ring during installation. Wipe the inside of the reservoir clear.

2. Oil the O ring in the groove on adapter.

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3.13

Hydraulics 3. Start the reservoir over the flange on the adapter up to the O ring. Make sure it is aligned properly with the holes as well as not cocked.

4. Rest a block of wood on the back of the reservoir and strike it squarely with a sharp blow in the center of the reservoir end. The reservoir should move into position.

5. Install four (4) screws in position and tighten to snug condition.

3.6.3

Cylinder Removal 1. Raise and block lifting frame of truck.

Release pressure in cylinder by activating lowering valve.

2. Disconnect and remove battery from unit to prevent accidental operation.

3. Remove electrical access cover, plastic cover.

4. Remove hydraulic line and pivot cylinder out of pocket.

5. Thoroughly clean outside of cylinder before removing hydraulic hose.

DANGER HOT OIL under pressure may be

present. Be certain truck is safely blocked and pressure is released.

Some spillage of hydraulic oil may occur.

6. Place on a clean bench for disassembly.

Cylinder Installation 1. In order to prevent air from filling the cylinder it is recommended to install the cylinder with rod retracted.

2. Install upper mount first and hold in place with shoulder bolt.

3. Connect hydraulic hose and use the pump to extend the cylinder.

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MARCH 1996

Hydraulics 4. Place bottom of cylinder in line with lower pocket.

5. Raise and unblock lifting frame of unit.

6. Install and connect battery to unit.

7. Test operation of cylinder and look for leakage around fitting and cylinder rod.

8. Install plastic cover and electrical access cover.

3.7 COMPONENT REPAIR 3.7.1

The pump has no serviceable parts. If repair is necessary a new pump should be installed.

3.7.2

Cylinder Disassembly 1. Thoroughly assembly.

clean

outside

of

cylinder

2. Pull rod out until end of rod and snap ring can be seen through inlet port.

3. Insert screwdriver in inlet port and slide snap ring in deep groove in rod assembly.

4. Remove rod assembly.

assembly

from

barrel

5. Remove wiper seal and seal from inside diameter of barrel assembly.

6. It is not necessary to inspect wiper seal, seal or lock ring. These parts should be replaced as new items and are included in the seal repair kit available for this cylinder.

Inspection 1. Thoroughly clean all parts and remove all nicks and burrs with emery cloth.

2. Inspect inside surface of barrel assembly for excessive wear or scoring.

MARCH 1996

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3.15

Hydraulics 3. Inspect outside surface of rod for nicks, scratches or scoring.

Assembly 1. All parts should be cleaned and dried thoroughly. Metal parts should be lightly oiled prior to reassembly.

2. Install new seal in inside diameter of barrel.

Install new wiper seal with lips facing inward to bottom of barrel.

3. Install new lock ring in deep groove of rod end.

4. Oil outside of piston rod and carefully insert rod in barrel assembly.

5. Push rod in barrel assembly until snap ring area of rod can be seen through port.

6. By using screwdriver through port, move snap ring to lock position.

7. Extend rod to full out position to make sure snap ring is locked in place.

3.16

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MARCH 1996

4.0 FRAME

MARCH 1996

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4.1

Frame CONTROL HANDLE HEAD ASSEMBLY

4.2

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MARCH 1996

Frame ITEM # NAME 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

MARCH 1996

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Reverser assembly Screw, self tapping Pin, roll Cam Return Spring, return Housing, switch Bushing Shaft, cam Control, thumb Pin, threaded Pin Grip, twist Bushing Block Screw, flat head locking Screw, socket (not part of handle assy.)

Guard Screw, shoulder Pin, roll Potentiometer and wires Gear Bracket, potentiometer Screw, machine Switch, forward Spacer Switch, rearward Nut Lockwasher Bracket, forward & rearward Heater, Cold Storage Switch, lower Screw, flat head Cover Switch, lift Spring, return Switch, horn Bracket, switch Nut Clamp, cable Harness, head Grip, fixed Washer Screw, flat head

# FOR ASSY. 1 6 3 1 1 1 1 2 1 2 2 2 2 2 2 2 2 1 1 1 1 1 1 2 1 1 1 2 2 1 1 1 9 1 1 6 1 1 1 1 1 2 2 2

UNITS

TWIST TWIST TWIST TWIST

THUMB THUMB THUMB

4.3

Frame LIFT FRAME AND CARRIER FRAME

4.4

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MARCH 1996

Frame ITEM # NAME 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 26 27 28 29 30 31 32 33 34 35

MARCH 1996

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Frame, lift (State Model & Serial Number) Bushing, iron Pin, wheel fork pivot Fitting, grease Wheel assembly, load Bearing Wheel, load Fitting, grease Pin, load wheel Fork, wheel Screw, set Pin, pull rod Bushing, iron Screw, hex locking Pin Rod, pull Pin, lower link Pin, lower link Link, lower Screw, hex locking Skid Link, lower Bolt, shoulder Link, upper Bushing, iron Screw, socket head, PMX Screw, socket head, QMX Frame, carrier (State Model & Serial Number) Bracket Nut, jam Screw, socket head Nut Guard, removable Nut, flange locking QMX Screw, flat locking QMX Hand rail assembly, QMX

# FOR ASSY. 1 4 2 21 2 2 1 2 2 2 10 2 16 4 2 2 2 2 2 4 2 2 4 2 2 1 2 1 1 2 2 2 1 4 4 1

4.5

Frame HAND RAIL ASSEMBLY, QMX

ITEM # NAME 1 2 3 4 5 6 7

4.6

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Cover Screw, flat locking Spring Switchbar, lift Switchbar, lower Nut Nut

# FOR ASSY.

ITEM #

NAME

1 6 8 1 1 2 2

8 9 10 11 12 13 14

Housing, switch Screw, Cap Bar, ride Bracket, switch Switchbar, horn Switchbar, high speed Harness, wiring

# FOR ASSY. 1 2 1 1 1 1 1

MARCH 1996

Frame RIDER PLATFORM, QMX

ITEM # NAME 1 2 3 4 5 6 7

Platform assembly Pad, left foot Pad, right foot Platform Screw, socket head Bushing Washer, machinery

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# FOR ASSY.

ITEM #

NAME

1 1 1 1 4 2 2

8 9 10 11 12 13 14

Bolt, shoulder Nut, flanged locking Screw, cap Caster Bumper Isolator Isolator

# FOR ASSY. 1 8 8 2 1 2 2

4.7

Frame 4.2 System Operation The PMX and QMX lowlift pallet truck uses a hydraulic cylinder coupled through a series of linkages to a lifting frame to lift the forks a maximum of nine (9) inches. Support at the ends of the forks is provided by the 5 inch wide load wheels. The lifting frame is designed so that the entire truck frame, with the exception of the transmission assembly and control handle, is raised with the pallet forks. Skids are mounted on the transmission frame to provide stability when the truck is fully raised.

4.3 Specifications Lowered height

3.25”

Raised height

9.25”

Load wheel dimensions

3.25” x 5”

Drive tire dimensions

10.5” x 5” x 6.5”

4.4 Maintenance and Adjustments Normal maintenance of the truck frame consists of lubricating the bushings on the lift linkages periodically. See Planned Maintenance Schedule. If the optional lube or cold storage package has not been fitted on the truck during production then lubrication consists of dripping 10 wt. machine oil onto the pivot points so that it soaks into the bushings. In wet or corrosive environments it will be necessary to reduce the time between planned maintenance intervals.

The only adjustment on the frame is the pair of lowered height stops. These consist of bolts with jam nuts fitted on the frame just above the transmission assembly on either side of the lifting cylinder. The bolts should be adjusted so that when the truck is fully lowered the bolt heads stop against the transmission frame evenly and both pallet forks are of equal distance from the floor.

4.8

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MARCH 1996

Frame 4.5 Troubleshooting Very little troubleshooting is necessary on the frame assembly. Most faults can be found by visual inspection. These usually are evidenced by unequal fork height or improper raised or lowered height.

The usual cause is wear in the bushings of the pull rod linkages connecting the rear of the fork frame to the load wheels. Other problems, such as slow raise and lower speeds and excessive noise during operation can also be caused by lack of lubrication which will lead to more serious problems is not quickly corrected. Occasionally a truck with unequal fork heights will be found to have been bent by overloading one fork. This condition may not be repairable.

4.6 Component Removal and Installation 4.6.1

Control handle head Remove the six Torx® head screws around the outer edge of the front switch bar cover on the control handle head. Do not remove the center screw. Lift the cover off. Remove two socket head screws accessible from inside the head assembly that bolt the head to the handle. Lift the head assembly away from the handle and disconnect the wiring harness plug before removing head from handle. Reassembly in reverse order.

4.6.2

Load wheels Disassembly and Repair LOAD WHEEL REPAIR AND REPLACEMENT The load wheel is a single wheel with a ball bearing at each end. Removal is accomplished by raising the forks to the maximum height.

Block the forks in a safe manner and remove set screw securing the axle shaft and remove axle.

When pressing bearings into the load wheel the sealed side of the bearing goes to the outside.

Install wheel and axle. Screw in set screw to lock axle in place.

MARCH 1996

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4.9

Frame 4.6.3

Pull Rod Bushings Removal and Replacement To replace pull rods and/or bushings it is easiest to work with machine upside down.

Remove battery before turning truck over.

Some hydraulic oil may leak from hydraulic reservoir.

1. Extend load wheel forks and remove shaft connecting wheel fork to pull rod.

2. Remove lower link (dog bone) stationary pivot pin by removing locking bolt.

3. With the lower links out of the lift frame channels the links can be separated and pull rod removed from link shaft. Each link has one shaft attached at opposite ends and link can be pulled apart without driving out any other roll pins.

4. Press new bushings in pull rods.

5. Re-assemble pull rods on lower links and press links together so they will fit in frame channel.

6. Re-install pivot shaft and retaining bolt in lower links.

7. Re-connect pull rod to wheel fork.

8. Place truck upright and install the battery, connect battery, test operation of the lift frame.

4.6.4

Carrier Frame Bushings The bushings on the upper links of the carrier frame can be replaced by removing the links from one side at a time and pressing in new bushings.

To replace the lower link bushings in the carrier frame it will be necessary to remove the pull rods and separate the lower links. New bushings can be pressed in the carrier frame.

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MARCH 1996

Frame To separate lift frame and carrier frame remove all electric connections and lift cylinder retainer plates from carrier frame before removing links.

Remove linkages and lift the lift frame off carrier frame.

4.6.5

Bumper Bushing (QMX ONLY) Reference page 4.7 1. Remove two (2) shoulder bolts (item #8).

2. Install new bushing (item #6).

4.6.6

Rider Platform Caster (QMX ONLY) Reference page 4.7 1. Remove tow (2) socket head screws (item #5).

2. Remove platform assembly (item #4).

3. Remove four (4) cap screws (item #10).

4. Replace caster.

4.6.7

Caster Wheel and Bearings (QMX ONLY) 1. Remove axle bolt for caster yoke.

2. Remove old wheel and bearings.

3. Install caster wheel and bearings.

MARCH 1996

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4.11