Page 1

Service Manual Chassis, Mast & Options EP10KRT EP12KRT EP15KRT

ETB10-00011-up ETB10-20001-up ETB10-50001-up

99759-65110


FOREWORD

This service manual is a guide to servicing of CatŽ lift trucks of 1.0 ton, 1.25 ton and 1.5 ton models. The instructions are grouped by systems to serve the convenience of your ready reference. Long productive life of your lift trucks depends to a great extent on correct servicing — the servicing consistent with what you will learn from this service manual. We hope you read the respective sections of this manual carefully and know all the components you will work on before attempting to start a test, repair or rebuild job. The descriptions, illustrations and specifications contained in this manual were of the trucks of serial numbers in effect at the time it was approved for printing. Cat lift truck reserves the right to change specifications or design without notice and without incurring obligation.

Safety Related Signs The following safety related signs are used in this service manual to emphasize important and critical instructions:

!

WARNING

!

CAUTION

NOTE

Indicates a specific potential hazard resulting in serious bodily injury or death. Indicates a specific potential hazard resulting in bodily injury, or damage to, or destruction of, the machine. Indicates a condition that can cause damage to, or shorten service life of, the machine.

Pub. No. 99759-65110


HOW TO READ THIS MANUAL Disassembly diagram (example)

Each disassembly diagram is followed by Disassembly sequence and Suggestion for disassembly.

Disassembly sequence

1 2

Cover, Bolt, Washer (part name) Output shaft (part name)

Suggestion for disassembly (1) Output shaft removal

Unit: mm Clearance between cylinder and piston

A

0.020 to 0.105

B

0.15

A: Standard value B: Repair or service limit


!

WARNING

SAFETY

!

WARNING

The proper and safe lubrication and maintenance for this lift truck, recommended by Cat lift truck, are outlined in the OPERATION & MAINTENANCE MANUAL for these trucks. Improper performance of lubrication or maintenance procedures is dangerous and could result in injury or death. Read and understand the OPERATION & MAINTENANCE MANUAL before performing any lubrication or maintenance.

The serviceman or mechanic may be unfamiliar with many of the systems on this truck. This makes it important to use caution when performing service work. A knowledge of the system and/or components is important before the removal or disassembly of any component. Because of the size of some of the truck components, the serviceman or mechanic should check the weights noted in this Manual. Use proper lifting procedures when removing any components. Following is a list of basic precautions that should always be observed. 1. Read and understand all warning plates and decals on the truck before operating, lubricating or repairing the product. 2. Always wear protective glasses and protective shoes when working around trucks. In particular, wear protective glasses when pounding on any part of the truck or its attachments with a hammer or sledge. Use welders gloves, hood/goggles, apron and other protective clothing appropriate to the welding job being performed. Do not wear loose-fitting or torn clothing. Remove all rings from fingers when working on machinery. 3. Do not work on any truck that is supported only by lift jacks or a hoist. Always use blocks or jack stands to support the truck before performing any disassembly.

!

WARNING

Do not operate this truck unless you have read and understand the instructions in the OPERATION & MAINTENANCE MANUAL. Improper truck operation is dangerous and could result in injury or death.

4. Lower the forks or other implements to the ground before performing any work on the truck. If this cannot be done, make sure the forks or other implements are blocked correctly to prevent them from dropping unexpectedly. 5. Use steps and grab handles (if applicable) when mounting or dismounting a truck. Clean any mud or debris from steps, walkways or work platforms before using. Always face truck when using steps, ladders and walkways. When it is not possible to use the designed access system, provide ladders, scaffolds, or work platforms to perform safe repair operations. 6. To avoid back injury, use a hoist when lifting components which weigh 23 kg (50 lb.) or more. Make sure all chains, hooks, slings, etc., are in good condition and are of the correct capacity. Be sure hooks are positioned correctly. Lifting eyes are not to be side loaded during a lifting operation. 7. To avoid burns, be alert for hot parts on trucks which have just been stopped and hot fluids in lines, tubes and compartments. 8. Be careful when removing cover plates. Gradually back off the last two bolts or nuts located at opposite ends of the cover or device and pry cover loose to relieve any spring or other pressure, before removing the last two bolts or nuts completely. 9. Be careful when removing filler caps, breathers and plugs on the truck. Hold a rag over the cap or plug to prevent being sprayed or splashed by liquids under pressure. The danger is even greater if the truck has just been stopped because fluids can be hot.


10. Always use tools that are in good condition and be sure you understand how to use them before performing any service work. 11. Reinstall all fasteners with same part number. Do not use a lesser quality fastener if replacements are necessary. Do not mix metric fasteners with standard nuts and bolts. 12. If possible, make all repairs with the truck parked on a level, hard surface. Block truck so it does not roll while working on or under truck. 13. Disconnect battery and discharge any capacitors (electric trucks) before starting to work on truck. Hang “Do not Operate� tag in the Operator’s Compartment. 14. Repairs, which require welding, should be performed only with the benefit of the appropriate reference information and by personnel adequately trained and knowledgeable in welding procedures. Determine type of metal being welded and select correct welding procedure and electrodes, rods or wire to provide a weld metal strength equivalent at least to that of parent metal. 15. Do not damage wiring during removal operations. Reinstall the wiring so it is not damaged nor will it be damaged in operation by contacting sharp corners, or by rubbing against some object or hot surface. Do not connect wiring to a line containing fluid. 16. Be sure all protective devices including guards and shields are properly installed and functioning correctly before starting a repair. If a guard or shield must be removed to perform the repair work, use extra caution. 17. Always support the mast and carriage to keep carriage or attachments raised when maintenance or repair work is performed, which requires the mast in the raised position.

18. Loose or damaged fuel, lubricant and hydraulic lines, tubes and hoses can cause fires. Do not bend or strike high pressure lines or install ones which have been bent or damaged. Inspect lines, tubes and hoses carefully. Do not check for leaks with your hands. Pin hole (very small) leaks can result in a high velocity oil stream that will be invisible close to the hose. This oil can penetrate the skin and cause personal injury. Use cardboard or paper to locate pin hole leaks. 19. Tighten connections to the correct torque. Make sure that all heat shields, clamps and guards are installed correctly to avoid excessive heat, vibration or rubbing against other parts during operation. Shields that protect against oil spray onto hot exhaust components in event of a line, tube or seal failure, must be installed correctly. 20. Relieve all pressure in air, oil or water systems before any lines, fittings or related items are disconnected or removed. Always make sure all raised components are blocked correctly and be alert for possible pressure when disconnecting any device from a system that utilizes pressure. 21. Do not operate a truck if any rotating part is damaged or contacts any other part during operation. Any high speed rotating component that has been damaged or altered should be checked for balance before reusing.


GROUP INDEX GROUP INDEX

Items involved

GENERAL INFORMATION

Serial Number Locations, Dimensions, Technical Data

1

VEHICLE ELECTRICAL COMPONENTS

Console Box, Key Switch, Lamp Specification Chart

2

MAIN CONTROLLER

Outline, Controller Components, Logic Card Components, Controller Models, Operation Outline, Drive System, Hydraulic System, Fail-safe System, Malfunction Detection, Malfunction Data Record, Setting, Self-diagnosis, etc.

3

TROUBLESHOOTING FOR CONTROL CIRCUITS

Faulty Central Vehicle Monitor System, Faulty Diagnosis Indication, or Other Abnormalities

4

MOTORS

Motor Installation Positions, Specifications, Structures, Tightening of High-power Cable Terminals, Inspection of Brushes for Wear and Brush Replacement, Procedures and Key Points for Removal and Installation, etc.

5

FRONT AXLE

Structure and Functions, Disassembly and Reassembly of Front Axle Assembly, Service Data

6

REAR AXLE

Rear Axle, Rear Wheels, Removal and Installation, Disassembly and Reassembly, Adjustment, Troubleshooting, Service Data

7

BRAKE SYSTEM

Specifications, Structure and Functions, Procedures and Key Points for Disassembly and Reassembly, Inspection and Adjustment, Troubleshooting, Service Data

8

STEERING SYSTEM

Specifications, Structure and Functions, Procedures and Key Points for Removal and Installation, Steering Control Valve, Hydraulic Circuit, Troubleshooting, Service Data

9

HYDRAULIC SYSTEM

Tank, Pump, Control Valve, Lift and Tilt Cylinders, Flow Regulator Valve, Down Safety Valve

10

MASTS AND FORKS

Simplex Mast, Duplex Mast, Triplex Mast

11

SERVICE DATA

Inspection Standards, Periodic Replacement of Parts, Lubrication Standards, Main Component Weights, Tightening Torque for Standard Bolts and Nuts, Special Tools

12

OPTIONS

Amber Strobe Kit, Back Buzzer Kit, Working Lamp Kit, Tire Kit

13


GENERAL INFORMATION 1 Vehicle Exterior ....................................................................................... Models ....................................................................................................... Serial Number Locations ...................................................................... Chassis and Mast Model Identification ............................................ Dimensions .............................................................................................. Technical Data .........................................................................................

1–1 1–1 1–2 1–3 1–4 1–5


GENERAL INFORMATION

Vehicle Exterior

103378

Models This manual applies to EP10KRT, EP12KRT and EP15KRT.

Truck Model

Serial Number

EP10KRT

ETB10-00011-up

EP12KRT

ETB10-20001-up

EP15KRT

ETB10-50001-up

1-1


GENERAL INFORMATION

Serial Number Locations

Mast number

Chassis number

Nameplate

209010

1-2


GENERAL INFORMATION

Chassis and Mast Model Identification

[Chassis] EP

10

KRT

Generation designator and truck type

Rated capacity 10: 1000 kg 12: 1250 kg 15: 1500 kg Battery type GP: gasoline engine DP: diesel engine [Mast] 2

G

15

CA

33

Maximum lifting height “33” stands for 3300 mm Order of the minor change (“CA” for the original, “CB” for the first change, “CC” for the second change, and so on) Applicable truck model designation 15: 1.0 ton class

Kind of mast G: simplex mast H: duplex mast J: triplex mast Major change (“2” for the original, “3” for the first change, and so on up to “9”)

1-3


GENERAL INFORMATION

Dimensions

209011

1-4


GENERAL INFORMATION

Technical Data Truck model

EP10KRT

EP12KRT

EP15KRT

Mast tilt, forward/backward

A (deg)

5/7

5/7

5/7

Height with mast lowered

B (mm)

2110

2110

2110

Standard free lift

C (mm)

120

120

120

Standard lift height

D (mm)

3300

3300

3300

3895

3895

3895

Overall height with mast raised (without backrest) E (mm) Overall length

F (mm)

2500

2500

2575

Length to fork face (includes fork thickness)

G (mm)

1700

1700

1775

Overall width

H (mm)

997

997

997

Forks dimensions (thickness × width × length)

I (mm)

35 × 80 × 800

35 × 80 × 800

35 × 80 × 800

Turning circle radius

J (mm)

1370

1370

1445

Fork carriage width

K (mm)

920

920

920

Ground clearance under mast, with load

L (mm)

80

80

80

100

100

100

Ground clearance center of wheelbase, with load M (mm) Travel speed, with/without load

km/h

11.5/13.5

11.2/13

11/12.5

Lifting speed, with/without load

m/s

0.29/0.48

0.27/0.48

0.26/0.48

Lowering speed, with/without load

m/s

0.52/0.50

0.52/0.50

0.52/0.50

1569/1667

1520/1669

1470/1670

4217/4315

4168/4315

4119/4314

Rated drawbar pull, with/without load (60 min. short duty)

N

Maximum drawbar pull, with/without load (5 min. short duty)

N

Gradeability, with/without load

%

5.5/8

4.5/7.5

3.5/6.5

Maximum gradeability, with/without load

%

13/20

11/18

10/16

Battery to DIN 43531/35/36A/B/C/No. Battery voltage/capacity at 5-hour discharge

DIN43535A V/Ah

Battery weight

kg

Truck weight, without load/including battery (Maximum battery)

kg

24/600, 720

24/600, 720

24/720, 840

445, 540

445, 540

540, 620

2333

2568

2778

Drive motor capacity (60 min. short duty)

kW

4.8

4.8

4.8

Pump motor output @15 % duty factor

kW

8.8

8.8

8.8

Drive motor control method

Mosfet-chopper

Pump motor control method

Chopper

1-5


VEHICLE ELECTRICAL COMPONENTS Console Box ............................................................................................. 2 – 1 Functions of Vehicle Monitor System ........................................................ 2 – 1 Electrical Components .............................................................................. 2 – 3 Disassembly and Reassembly .................................................................. 2 – 4

Direction Lever ........................................................................................ Accelerator Control ............................................................................... Key Switch ............................................................................................... Lighting Switch ....................................................................................... Fuses ......................................................................................................... Lamp Specification Chart .................................................................... Electrical System Diagram (Type: Chopper) ................................... Electrical Schematic (Type: Chopper) .............................................. Electrical Schematic (Type: Chopper) ..............................................

2– 5 2– 6 2– 7 2– 7 2– 8 2– 8 2– 9 2 – 11 2 – 13

2


VEHICLE ELECTRICAL COMPONENTS

Console Box 1 2 3 4

Vehicle monitoring system (VMS) Steering tilt knob Key switch Lighting switch

103380

Functions of Vehicle Monitor System (VMS)

209140C

Operations

No.

Monitor name

1

Service indicator

2

Worn motor brush Drive motor and pump motor Worn brushes lamp brushes in operable condition

After brushes are replaced, lamp turns OFF.

3

Service indicator Controller, drive motors and Overheat pump motor in normal temperature

Error code is indicated on display 8 when overheating condition has occurred.

4

Remaining battery charge warning lamp

5

Brake fluid level lamp

6

Parking lamp

When OFF

When ON or flashing

Remarks

Wrench-symbol warning lamp turns on when error has occurred.

Normal battery condition

Red LED turns on. Drive 1: Lifting function operates in restricted mode. Normal fluid level

Parking brake disengaged

Parking brake engaged 2-1

Low fluid level


VEHICLE ELECTRICAL COMPONENTS

No. 7

Monitor name

When OFF

Malfunction lamp Normal

Vehicle malfunction

Any of four green LEDs turns on when corresponding battery is discharged.

Battery discharge indicator (BDI)

9

10

Hourmeter time display

11

Truck mode indicator

Remarks

Error code is displayed as follows when an error is present. A L × × ×

Error indicator

8

When ON or flashing

Power mode (Mode B)

Economy mode (Mode A)

Error indicator

Indication

Condition

A L 0

7

9

ON

Key switch turned [ON] with direction lever in [F] or [R] position

A L 0

6

5

ON

Drive motor overheated

A L 0

1

7

ON

Pump motor overheated

A L 0

6

2

ON

Traction controller overheated

A L 0

0

6

ON

Data communication error

A L 0

3

5

ON

Pump motor overcurrent

A L 0

6

4

ON

Hydraulic controller overheated

A L 0

7

2

ON

Drive motor stall timer

A L 0

7

9

ON

Faulty setting of tilt lever

A L 0

7

9

ON

Faulty setting of attachment lever 1

A L 0

7

9

ON

Faulty setting of attachment lever 2

A L 0

3

2

ON

Regeneration diode error

A L 0

3

2

ON

Drive motor armature diode error

A L 0

2

8

ON

Pump motor armature diode error

A L 0

6

9

ON

Drive motor armature overcurrent

A L 0

5

7

ON

Drive motor field overcurrent 2-2


VEHICLE ELECTRICAL COMPONENTS

Electrical Components

209141

1 2 3 4

Key switch Display Horn Controller

5 6 7 8

2-3

Contactor Fuse holder Plate Rivet


VEHICLE ELECTRICAL COMPONENTS

Disassembly and Reassembly Disassembly

209142

Sequence 1 2

Console box (front panel) Forward/reverse lever

3 4

Console box (rear panel) Steering column assembly

Disassembly procedure (1) Remove the rear panel and front panel from the steering column assembly. (2) Disconnect the harness connector at the direction lever. (3) Disconnect the harness connector at the horn. (4) Remove the steering tilt knob from the rear panel of the console box. (5) Remove the steering column assembly. 209143

Reassembly Follow the disassembly procedure in reverse.

2-4


VEHICLE ELECTRICAL COMPONENTS

Direction Lever Structure

209144

1 2 3

Knob Lever Harness

4 5

2-5

Connector Screw, Spring washer


VEHICLE ELECTRICAL COMPONENTS

Accelerator Control

206805A

Adjustment procedure (1) Disconnect the battery plug. (2) Adjust the stopper bolt to a fixed position of 32 to 34 mm from the floor to the top head of the bolt. (3) Adjust the mounting angle of the position meter using the adjusting screws so the switch inside the position meter turns on when the accelerator pedal is depressed 1.5 to 2.6 mm. Make sure the inside switch turns ON by checking the continuity between terminals 143 and 144 with an ohmmeter. (4) Perform the accelerator self-diagnostics according to the table on page 3-13. The display should read OFF and Speed 0 without the accelerator depressed. The display should change to ON before the speed changes from 0 to 1. If not, then readjust accelerator switch. (5) Make sure when the accelerator is fully depressed when the display reads Speed 16. If not, readjust the stop per bolt. 2-6

208081


VEHICLE ELECTRICAL COMPONENTS

Key Switch Terminal

B

M1, M2

Connection destination

Main fuse battery

Logic card

(OFF)

I (ON)

206806A

Lighting Switch Terminal Connection destination

B

W

H

Battery

Working lamp

Head lamps

1st position 2nd position

103042

209145

2-7


VEHICLE ELECTRICAL COMPONENTS

Fuses Capacity (A)

Location

Main connecting device

500

Battery Contactor assembly

Refer to “Group 3 Main Controller”.

325

Loading hydraulic motor

15

Electric parts

Fuse holder

10

Controller 103402

NOTE Refer to Parts Manual for proper replacement fuses.

Lamp Specification Chart Item

Bulb Quantity Bulb color

Lamp

Remarks 24 V

External diagram

Head lamps

2

Clear

70 W

Option

Working lamp

1

Clear

70 W

Option

205833

2-8


MAIN CONTROLLER Variation....................................................................................... Outline of Controller .................................................................... Outline of Contactor Module....................................................... Operation Outline ........................................................................ Drive System ...............................................................................

3– 1 3– 3 3– 4 3– 5 3– 5

Neutral Position ........................................................................................ 3 – 5 Powering ................................................................................................... 3 – 5 Regeneration System ............................................................................... 3 – 6

Hydraulic System ........................................................................ 3 – 9 Fail Safe System.......................................................................... 3 – 10 Output Power Control at Low Battery Voltage ........................................... 3 – 10 Overheat ................................................................................................... 3 – 10 Maximum Vehicle Speed Control .............................................................. 3 – 10 Output Power Control During Braking ....................................................... 3 – 10 Chat Timer ................................................................................................ 3 – 10 Seat Switch Timer ..................................................................................... 3 – 10 Stall Timer ................................................................................................. 3 – 11

Malfunction Detection (Run Time Diagnostics) .......................... 3 – 11 Malfunction Data Record (History Folder) .................................. 3 – 11 Data Storage ............................................................................................ 3 – 11 Review of Stored Data .............................................................................. 3 – 11

Setting ......................................................................................... Self-diagnostics .......................................................................... Safety Function ........................................................................... Display ........................................................................................

3 – 11 3 – 11 3 – 12 3 – 16

Combination Display ................................................................................. 3 – 16 Action Lights ............................................................................................. 3 – 16

3


Removal and Installation............................................................. 3 – 17 Removal and Installation of Controller ...................................................... 3 – 17 Removal and Installation of Logic Card ..................................................... 3 – 19

Basic Check ................................................................................ 3 – 20 Testing Tools ............................................................................................. 3 – 20 Measurement of Logic Card Voltage ......................................................... 3 – 20 Check Contactor Coil ................................................................................ 3 – 22 Check Contactor Tip ................................................................................. 3 – 22 System Construction ................................................................................. 3 – 23 Controller Interface Pin Assign ................................................................. 3 – 24

Digital Console ............................................................................ 3 – 25 Programming and Adjustments Using Digital Console .............................. 3 – 25 Combisem Diagnostic ............................................................................... 3 – 35 Digital Console Function Diagram ............................................................. 3 – 45


MAIN CONTROLLER

Variation (1) There is one controller model, as shown in the table below. Voltage

Controller

Configuration

DC24 V

Chopper

–

(2) There is one controller and one contactor module. Item

Remarks

Traction

24 V 500 A max.

Controller Hydraulic 24 V 550 A max. Contactor

Line contactor, fuse (drive and pump) and switches

(3) The maximum vehicle speed varies depending on load weight, as shown in the table below. Unit: km/h Truck model

EP10KRT

EP12KRT

EP15KRT

Travel speeds with load

11.5

11.2

11.0

3-1


MAIN CONTROLLER

Outline of Controller The controller is the heart of the truck operating system. The logic card contains decision making functions, and is equipped with a battery discharge indicator and a malfunction diagnostic function. The controller is used to operate the drive motor and hydraulic motor.

209026

1 2 3 4

Controller Logics assembly Cover Screw

5 6 7

3-3

Washer Spring washer Connector


MAIN CONTROLLER

Outline of Contactor Module The contactor module controls the function of the main switch and circuit protector. The contactor is operated by the controller.

209027

1 2 3 4

Bracket Contactor Bar Terminal, Nut

5 6 7

3-4

Pump fuse (350 A) Main fuse (500 A) Screw, Washer


MAIN CONTROLLER

Operation Outline

Drive System

(1) Power ON, default condition

Neutral position

Turning on the key switch supplies power to the controller. When power is ON, the controller checks all switches and sensor input conditions; the combination display indicates the vehicle condition.

If the truck runs and the direction lever is in the neutral position, then the regeneration function is activated. If the truck is powered by turning the key switch to ON and the direction lever is in the neutral position, the controller checks whether the drive motor is turning or not.

Next, the line contactor turns ON and provides battery power to the main circuit. The pump motor starts rotating (idle revolution is 500 to 600 rpm). Seat switch: ON

Powering

Forward/reverse lever: Neutral

(1) Outline

Accelerator is a combination of the digital signal (accelerator idle switch) and the analog signal (accelerator input). Digital signals relationship to analog signal.

Hydraulic lever: OFF Accelerator: Neutral

• Analog signal range is from 0 to 5 V. • Digital signal voltage change (open ↔ close) is typically 0.94V ± 0.47V.

With the line contactor in the ON condition, the hourmeter indicates cumulative hours.

During vehicle operation the signal voltage ranges from where the accelerator idle switch is closed (typically 0.94 V ± 0.47 V) to about 4 V.

(2) Normal mode (RUN mode)

When the direction lever is operated and the accelerator pedal is pressed, the vehicle moves forward or backward. During deceleration, the motors conduct various regenerative operations according to the settings.

Its signal range can be adjusted by using the console. The controller uses this signal as continuous input data. Accelerator signal is a torque demand data.

When the vehicle is running, the steering pump motor rotates at 700 to 800 rpm.

Motor torque is determined by accelerator signal and vehicle speed.

Operating a hydraulic lever activates the pump motor and provides hydraulic power.

Power selection can be selected by using the console. Current rise rate can be adjusted by using console.

The controller monitors operating conditions. When an abnormality occurs, the display unit indicates an error code and activates an appropriate fail-safe function. The error code is stored in the controller memory; the combination display indicates the error code.

(2) Truck mode

The truck mode can be selected from Power Mode (Mode B) and Economy Mode (Mode A) by using the console. Each Mode has preset values for drive speed, acceleration, lift speed, tilt speed, and regen brake. For reference, performance changes of 1.5 ton class are shown below.

3-5


MAIN CONTROLLER

Truck Mode Item

1.5 ton class Economy Mode

1.5 ton class Power Mode

Drive speed (without load)

0 to 10.0 km/h

0 to 12.5 km/h

Acceleration

Comfortable

Fast

Lift speed (without load)

0 to 0.42 m/s

0 to 0.48 m/s

Fixed

Fixed

Moderate braking

Hard braking

Tilt speed Regen brake

In the weakening region, the speed of the motor can be reduced by increasing the flux. Consequently EMF will be increased and current direction will be in the opposite direction, so the battery is charged by the dynamic energy of the vehicle.

Regeneration System Basic theory The Electro Motive Force (EMF) on the rotor of a Separately Excited Machine motor (SEM motor) is proportional to the rotating speed of the rotor and to the flux generated by the field current. Rotating speed is dependent on truck speed and field current which can be changed by the controller.

This condition happens during deceleration when the accelerator pedal is depressed from 100% to 70%. At 70%, the speed reaches o its nominal speed and the system comes out from the weakening region. Nominal speed means the motor speed at nominal flux and at nominal voltage (equal to the battery voltage).

During traction, the Maximum EMF is equal to or less than the ones applied to the rotor current. Some rotor current losses are due to external cables, bad connections and brushes. Under the same flux volume, the rotating speed will decrease when motor torque become high and the rotating speed will reach the maximum value with zero rotor current.

Once the motor reaches nominal speed, more braking is needed (Ex. Accelerator pedal is completely released), the controller should reduce the applied voltage to the rotor from 100% down to 0%. As soon as the rotor is short-circuited, the EMF will be equal to 0 and the rotation speed will be zero (or almost equal to zero). By reducing the applied voltage to the rotor, the controller should turn ON the drive MOSFET (minus battery side) and turn off the brake MOSFET (plus battery side) with the high time ratio (the two changing conditions are written below respectively). The direction of the motor current during this phase is shown in Fig. 1 and 2 where the current into the motor is in the opposite direction to the traction current direction (battery plus to minus).

When the motor is raced at high speed, the EMF will be higher than the applied voltage. Resulting in the rotor current flowing in the opposite direction. In this condition, the motor will brake automatically and recharge the battery. SEM motor is able to transform its function between motor and generator (brake); behavior will depend on the ratio between the required speed and the real motor speed.

It follows two different conditions:

At the right load condition, the speed of the motor can be increased automatically with reducing the flux. This working condition is called the weakening region.

3-6


MAIN CONTROLLER

Stator

Drive MOSFET ON Drive motor

Rotor

Brake MOSFET OFF

1) Regenerative condition: The current comes from minus battery, through the drive MOSFET and then through the motor to recharge the battery.

Fig.1 Regenerative condition

3-7


MAIN CONTROLLER

Stator

Drive MOSFET OFF Drive motor

Rotor

During regenerative condition, the rotor current runs out rapidly and should be incremented by changing to the short-circuit condition (during the short-circuit condition the rotor current increases rapidly by EMF). The inductance of the system gives the necessary inertia for the flow of constant current.

Brake MOSFET ON

2) Short circuit condition: The current flows through the rotor via the closed brake MOSFET.

Fig.2 Short circuit condition

3-8


MAIN CONTROLLER

Function

(5) Anti roll-down

When the vehicle is on a downward grade with the key switch ON and running over maximum speed, then regeneration is activated.

(1) Lever regeneration

When the direction lever is shifted into the position opposite to the vehicle's traveling direction, the regeneration function is activated. The amount of regeneration is determined by the truck speed and the accelerator position.

Hydraulic System

The regenerative characteristic can be selected by using the console. The degree of acceleration serves as the parameter. The harder the accelerator pedal is pressed, the amount of regeneration increases.

When the hydraulic lever is operated, the pump motor rotates. The motor is driven by a specified chopping rate.

The regeneration function is activated until the vehicle stops.

(1) Lift speed

When the lift lever is operated, the lift analog signal changes continuously.

The maximum current of regeneration must be less than the powering current.

Lift potentiometer is the stroke sensor.

(2) Neutral regeneration

In the operating condition, lift signal range is from 1 V to 4 V.

When the direction lever is shifted into the neutral position, the regeneration function is activated.

Signal range data can be adjusted by using the console.

The regenerative characteristic can be selected by using the console.

The controller uses this signal for continuous input data.

The regeneration function is activated until the vehicle stops.

(2) Tilt speed

The maximum current of regeneration must be less than the powering current.

Tilt speed is set by the controller. This function cannot be adjusted by using the console.

(3) Accel regeneration (auto regeneration)

(3) Attachment 1 speed, attachment 2 speed

When the direction lever position is the same as the vehicle's traveling direction and the accelerator is released, then the regeneration function is activated.

The attachment speed function is set by a priority for each attachment. These functions can be adjusted by using the console.

The regeneration character is determined by auto regenerative characteristics and can be selected by using the console. The maximum current of regeneration must be less than the powering current.

(4) Priority

When two or more levers are operated at the same time, the following priority order is effective. Tilt lever (high priority), Attachment 1 lever, Attachment 2 lever, lift lever (low priority)

The regeneration function is activated until the vehicle stops. (4) Anti roll-back

When the vehicle runs with the key switch ON and the accelerator position is in neutral, then regeneration is activated.

3-9


MAIN CONTROLLER

Fail Safe System

(3) Controller overheat

When powering, the controller restricts the drive motor operation to the extent that the trucks can travel with a full load. The output duty of lift and attachment 1and 2 is cut by 50%.

Output Power Control at Low Battery Voltage (1) Battery discharge characteristic

Available for the different discharge characteristics of the battery. It can be adjusted by using the console.

Maximum Vehicle Speed Control Limits the maximum vehicle speed.

(2) Output power control

Output Power Control During Braking

When the battery voltage is lower than the setting data, this limits the output power. [Output power controls]

The maximum current is controlled during the use of the service brake and parking brake.

Traction: When powering, limits the output power.

(1) Service brake

Under the condition of full load, the vehicle can run.

Maximum field current:

20A

Maximum armature current: 125A

Pump: The operation of lift and attachment 1and 2 to cut their output duty ratio by 50%. Tilt operation remains the same.

(2) Parking brake Maximum field current:

20A

Maximum armature current: 125A

When operated at the same time: The pump motor can operate only when the truck stops and the direction lever is in neutral. Battery voltage ranges from 15 to 18 at this time. Output controls are as follows.

Chat Timer When the following conditions remain for the time duration setting, the pump motor stops.

[Output power control] Traction: When powering, limits the output power. Under the condition of full load, the vehicle can run.

(1) Accelerator:

0

(2) Forward/reverse lever:

Neutral

(3) Lift, tilt and attachment levers: OFF

Pump: Doesn't control output.

(4) Steering:

Not operated

Line contactor is OFF when battery voltage is under 15 V. Reset the key switch to the ON position.

Operating any of the above, except (4), activates the pump motor. Chat timer can be selected by using the console (5 to 40 sec).

Seat Switch Timer

Overheat

When the operator leaves the seat for the time duration setting, the line contactor turns OFF. When the key switch is turned on without the operator sitting in the seat, the line contactor turns OFF.

(1) Drive motor overheat

When powering up, the controller restricts the drive motor operation to the extent that the trucks can travel with full load.

If acceleration is 0, direction lever in in neutral and the hydraulic levers are all OFF, turning on the seat switch activates the line contactor.

(2) Pump motor overheat

The output duty of lift and attachment 1 and 2 is cut by 50%.

Seat switch timer can be set by using of console (3 to 15 sec). 3-10


MAIN CONTROLLER

Stall Timer

Setting

Stall timer will be pre-set at 10 sec to protect the motors from overheating.

Use serial communication, and operate console tool. Truck mode

This setting is adjustable by using the console.

The truck mode can be selected between Power Mode (Mode B) and Economy Mode (Mode A) using the console.

Malfunction Detection (Run Time Diagnostics)

Setup parameter

Standard setup parameters, can be selected by using the console tool. Every parameter can be setup in 10 steps. Final definition of parameters are the result of prototype testing.

If a malfunction is detected, the red LED flashes and the error code is indicated on the combination display. The corresponding fail-safe is activated at the same time.

(1) Drive speed (2) Acceleration

Refer to the malfunction detection tables. Customer should inform service of all malfunction error codes and LED flash patterns.

(3) Regen braking (auto-regen, direction regen, neutral regen) (4) Lift speed (5) Attachment speed 1

Malfunction Data Record (History folder)

(6) Attachment speed 2

Data Storage

(8) Chat timer (3 to 15 sec)

(7) Seat switch timer (5 to 40 sec)

Errors are automatically stored in the memory. A maximum of 5 sets of data can be stored.

Self-diagnostics Review of Stored Data

Check the input and output status. Use serial communication, and operate console.

(1) To review data

Use serial communication, and operate console. (2) To delete data

Use serial communication, and operate console.

3-11


MAIN CONTROLLER

Safety Function The controller must meet the safety conditions below: (1) When the CPU is hanging up, the vehicle will stop functioning. (2) When the accelerator condition is unusual, the vehicle should be stopped. (3) It has a function that protects against motor and contactor short circuits. (4) If forward and reverse signals turn on at the same time, the vehicle must stop. (5) If something unusual happens, it indicates the status. (6) Even if a terminal of the controller makes contact with a high voltage line or grounding line, the controller will not crash nor run out of control. (7) When a different battery voltage is connected, the controller indicates the status. (8) When the lift potentiometer signal is unusual, the lift function will stop.

3-12


MAIN CONTROLLER Malfunction Detection Display LED Detection method/condition Error Brake Battery Thermal Brush

Malfunction

Error code

Fail-safe process

Reset method

Drive motor overheat

Signal input

*

AL065

Output power control Cooling

Pump motor overheat

Signal input

*

AL017

Output power control Cooling

Controller overheat

Signal input

AL062

Output power control Cooling

*

Drive motor brush wear

*

Pump motor brush wear

*

Brake fluid low

*

Drive motor transistor wire breakage

Check the main circuit voltage level

*

AL060

Line contactor OFF

Power reset

Drive motor transistor shorting

Check the main circuit voltage level

*

AL032

Line contactor OFF

Power reset

Drive motor stall timer

Time duration elapsed

*

AL072

Line contactor OFF

Power reset

Drive motor transistor drive error

Error detection signal from drive card *

AL060

Line contactor OFF

Power reset

Drive motor current sensor error

Check the current sensor output value *

AL053

Line contactor OFF

Power reset

Drive motor armature over current

500 A

*

AL069

Line contactor OFF

Power reset

Drive motor field over current

50 A

*

AL057

Line contactor OFF

Power reset

Drive motor field error

Compare the current instruction value * and actual current valve

AL058

Line contactor OFF

Power reset

Drive motor field drive error

Error detection signal from H bridge card

*

AL015

Line contactor OFF

Power reset

Pump motor transistor wire breakage Check the main circuit voltage level

*

AL028

Line contactor OFF

Power reset

Pump motor transistor shorting

Check the main circuit voltage level

*

AL028

Line contactor OFF

Power reset

Pump motor transistor drive error

Error detection signal from drive card *

AL028

Line contactor OFF

Power reset

Pump motor current sensor error

Check the current sensor output value *

AL056

Line contactor OFF

Power reset

Pump motor over current

500 A

*

AL035

Line contactor OFF

Power reset

Line contactor error

Check the main circuit voltage level

*

AL037

Line contactor OFF

Power reset

Regeneration diode error

Check the main circuit voltage level

*

AL032

Line contactor OFF

Power reset

Drive motor armature diode error

Check the main circuit voltage level

*

AL032

Line contactor OFF

Power reset

Pump motor armature diode error

Check the main circuit voltage level

*

AL028

Line contactor OFF

Power reset

Drive motor armature breakage

Check the main circuit voltage level

*

AL032

Line contactor OFF

Power reset

Pump motor armature breakage

Check the main circuit voltage level

*

AL028

Line contactor OFF

Power reset

Accelerator error

Input range exceeded

*

AL078

Line contactor OFF

Power reset

3-13


MAIN CONTROLLER Display LED Detection method/condition

Reset method

Error code

Fail-safe process

Forward/reverse lever or acceleration When lever is not in neutral or setting error acceleration is not 0 at power ON

AL080

Line contactor OFF

Power reset

Seat switch setting error

When signal is not input at power ON

AL079

Line contactor OFF

Switch ON

Tilt lever setting error

When signal is input at power ON

AL079

Line contactor OFF

Switch OFF

Attachment 1 lever setting error

When signal is input at power ON

AL079

Line contactor OFF

Switch OFF

Attachment 2 lever setting error

When signal is input at power ON

AL079

Line contactor OFF

Switch OFF

Lift potentiometer error

Input range exceeded

Line contactor OFF

Power reset

Data communication error

The display indicates an error code * when there is no data communication.

AL006

Display

Power reset

*

AL013

Line contactor OFF

Power reset

Line contactor OFF

Power reset

Error Brake Battery Thermal Brush

Malfunction

*

E2PROM error Controller error

ROM and RAM check at power ON

Battery voltage low

The battery voltage is lower than 15 V * at power ON

AL055

Line contactor OFF

Power reset

Battery voltage high

The battery voltage is higher than 36 V at power ON

AL059

Line contactor OFF

Power reset

Battery voltage low

When the truck is working, the battery voltage from 15 V to 18 V

*

AL068

Output power control Voltage recovered

Battery voltage low

When the truck is working, the battery voltage lower than 15 V

*

AL067

Line contactor OFF

3-14

*

*

Power reset


MAIN CONTROLLER

(6) Maintenance alarm function

Display

Hour glass symbol shows the request of programmed maintenance or the state of Alarm. In this case the relative code will be displayed.

Combination Display The combination display communicates with the controller and functions as indicated below. Its power is supplied from the controller. (1) BDI (Battery discharge indicator) function Five LEDs, show the battery’s State of Charge. Four Green, and one Red. With a fully charged battery, all the Green LEDs are illuminated. As the battery becomes discharged, the Green LEDs turn off progressively, one after the other, in proportion to the residual charge of the battery, until value of residual charge is reached. At this time the Red LED illuminates indicating a discharged battery.

Action Lights (1) Brush wear indicator: Drive motor, pump motor Indicates when the the drive motor or pump motor brush becomes worn. (2) Brake fluid indicator

(2) Hourmeter function

Indicates when the brake fluid level become low.

Hourmeter indicates cumulative line contactor ON hours. When the hourmeter is working, hourglass symbol flashes.

(3) Parking brake Illuminates when the parking brake is being applied.

(3) Error code display function The display shows an error code and flashes red LED when an abnormality occurs. (4) Truck mode display function The display shows the turtle symbol when Economy Mode (Mode A) is selected.

(5) Software version display function When the Key Switch is initially closed, the display shows the EPROM Version for a few seconds. (EPXXX where XXX represents the version). Simultaneously the symbol of a Shifting Spanner appears.

3-16


MAIN CONTROLLER

Removal and Installation Removal and Installation of Controller

!

WARNING

Disconnect the battery plug before performing maintenance on the controller.

(1) Removal of rear cover

(a) Turn the key switch off. (b) Disconnect the battery plug. (c) Remove the rear cover of the counterweight. (2) Removal of controller

!

CAUTION

Be sure to regularly check the tightened torque of high-tension battery cable terminals. If the cables are loosely connected, excessive contact resistance can cause over-heating or lead to a fire in a worst case scenario. When checking or adjusting the cable routing, avoid pulling the cable. If cables move even slightly at the terminals, loose connections will result. While working with the cables be sure to tighten the terminal connections.

209029

Remove the power cables (for battery and motors). Tightening torque for stud terminal (M6)

11.8 ± 2.0 N·m (1.2 ± 0.2 kgf·m)

(a) Note that a flat washer and a disc spring are installed on each connector terminal. (See the illustration at right.)

209030

3-17


MAIN CONTROLLER Disconnect connectors CNA, CNB and CNC

NOTE Hold the connectors to unplug. Do not pull the harnesses to disconnect the connectors.

209031

Remove the controller mounting screws (M8: 4 places for controller), and remove the controller.

209032

(3) Installation of controller

Follow the removal procedure in reverse.

NOTE There is thermal paste between the counterweight and the controller. It is important for cooling the controller. Spread the thermal paste evenly before mounting the controller on the counterweight.

209033

3-18


MAIN CONTROLLER

Removal and Installation of Logic Card (1) Removal of controller cover

Remove the cover mounting screws (M4: 3 places), and remove the controller cover.

209034

(2) Removal of logic card

(a) Disconnect J1, J2 and J3. (b) Remove the logic card bracket mounting screws (M4: 2 places), and remove the logic card with bracket. (c) Remove the logic card mounting screws (M3: 5 places), and the heat-sink mounting screws (M4: 2 places behind the bracket), and remove the logic card.

(3) Installation

Follow the procedure in reverse.

209035

3-19


MAIN CONTROLLER

Basic Check Always following basic troubleshooting steps. • Talk to the operator. • Confirm his description of the problem with an operational check. • Visually inspect cables, connectors, contactor tips, etc. • Perform basic battery cables to frame resistance test. (at least 20 k ohm) • Check battery condition. Always check each option and write down the reading.

Testing Tools (a) (b) (c) (d)

Circuit tester Clamp meter IC tip Digital console (Refer to Page 3-25.)

(b) (a) (c)

NOTE The illustrations show digital circuit testers. In these testers, the positive (+) terminal is applied with positive charge, and the negative (-) terminal with negative charge. It should be noted that the terminals must be connected inversely when using an tester.

!

208282

WARNING

Disconnect the battery plug before inspecting or adjusting the controller.

Measurement of Logic Card Voltage

!

WARNING

To prevent accidental movement of the vehicle, place wood blocks under the vehicle to lift the rear wheel off the ground. Do not stand close to the rear wheel.

3-20

209036


MAIN CONTROLLER

(a) Place wood blocks under the vehicle to lift the rear wheel off the ground. (b) Turn the key switch off. (c) Disconnect the battery plug. (d) Remove the rear cover from counterweight. (e) Reconnect the battery plug. (f) Turn the key switch on. Connect the negative terminal of the circuit tester to the NEG terminal of the controller. (g) Set the circuit tester to the 50- or 100- VDC range. (h) Connect the positive terminal of the circuit tester to each pin of connectors CNA, CNB and CNC.

NOTE Be careful not to short circuit pins. For the normal voltage value, refer to the logic card voltage chart on the following pages.

3-21


MAIN CONTROLLER

Check Contactor Coil

!

CAUTION

Disconnect the battery plug before close the controller.

Disconnect the lead wire of coil. Set the circuit tester to 200 ohm range. Measure coil resistance. • If the measured value deviates from the above range, replace the contactor assembly. With the lead wire of contactor coil connected, set the circuit tester to 200 VDC range. Connect the negative (-) terminal of the circuit tester to the negative-side coil terminal (small fasten terminal) and the positive (+) terminal of the circuit tester to the positive-side coil terminal (large fasten terminal). Connect the battery, and operate the control device that activates the contactor. The circuit tester should indicate a value between 23.4 to 52 V after the contactor is in operation. If contactor resistance is found to be normal during the coil resistance test, but the measured voltage is not within the 23.4 to 52 V range, replace the logic card.

Check Contactor Tip Turn key switch off. Disconnect battery plug. Check voltage of contactor terminal. Check the tip condition and the movement. Check the gap. • If the contactor shows any fault, replace or correct the contactor.

209037

3-22


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Caterpillar cat ep12krt forklift lift trucks chassis, mast and options service repair manual sn:etb1  
Caterpillar cat ep12krt forklift lift trucks chassis, mast and options service repair manual sn:etb1  
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