90 minute read
Technical specifications
maintenance section in Chapter 4 Electrical operation and maintenance for more information.
3.4.3. Checking the truck for external damage
Visually check the truck for any apparent problems or external damage. If damage is apparent, its extent should be checked and any necessary repairs made before continuing with regular maintenance. If the damage in any way affects the use or safety of the truck, the truck must be taken out of use until it is fully operational.
3.4.4. Checking the condition of the wheels
The truck has three wheel types: drive, load and castor.The drive wheel is located immediately under the tiller arm anchoring point and supports a considerable portion of the truck’s weight. It is attached to the drive motor via the transmission to propel the truck, and it is turned with the tiller arm to steer the truck.
Figure 3.4. Drive wheel
The load wheels are located near the ends of the forks.Their main purpose is to support the weight of the load. Depending on
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the truck model, there is either a single or a double load wheel in each fork.
Figure 3.5. Load wheels
The side-supporting castor wheels are located under the main chassis on either side of the drive wheel.They support the truck when it is driven and prevent it from tilting, as there is only one drive wheel.The castor wheels turn automatically to follow the direction of travel.They are equipped with suspension springs.
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Figure 3.6. Castor wheel
Remove the main cover to gain better access to the wheels. Check all the wheels on a truck for damage and wear.The wheels should wear evenly, and there should be no flats or holes in the wear surface.The wheels should also turn smoothly on their axles and there should not be play in the bearings. Even wear can be tested by driving the truck on a smooth surface to test that all the wheels turn and the truck rides smoothly. If a wheel or a bearing has sustained damage that affects use or if its surface has worn completely, it should be replaced. Refer to Chapter 6 Mechanical maintenance for information on replacing and servicing wheels.
3.4.5. Checking that the batteries are securely fastened
The fastening of the batteries depends on the truck model.The 1,300 kg capacity truck does not have a separate battery compartment. Its two service-free batteries are located within the main chassis, on both sides.These batteries are held in place by straps. Open the main cover to perform this check. Check that the straps are tight and that both batteries are securely held in place.
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Figure 3.7. Battery arrangement on 1,300 kg capacity trucks
Trucks with a capacity of 1,600 and 2,000 kg have a separate battery compartment between the main chassis and the forks. On the 1,600 kg capacity truck, the battery assembly sits in its well and is kept in place by its own weight.The implementation is similar on the 2,000 kg capacity truck, but the battery assembly is also held in place with a fixing bracket. Open the battery compartment cover to check the battery assembly. In both cases, check that the battery assembly sits evenly at the bottom of the battery well. Check that the bracket is securely fixed on the 2,000 kg capacity truck.
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Figure 3.8. Battery arrangement on 1,600 and 2,000 kg capacity trucks
3.4.6. Checking the level of battery fluid in each cell
NOTE
This check applies only to the 1,600 and 2,000 kg capacity trucks with wet batteries.The 1,300 kg capacity truck has service-free batteries. Make sure that the battery is fully charged before checking the level of battery fluid.
Take appropriate precautions when handling batteries and battery fluid. Battery fluid is a corrosive acid solution and can cause burns if it comes into direct contact with bare skin. Use only approved fluid to fill the battery cells. Refer to Section 3.9 Lubricant and fluid recommendations for fluid recommendations.
Open the battery compartment cover to access the battery cells. Follow the instructions issued by the battery or battery cell manufacturer for maintaining battery cells in good condition. Use care not to contaminate the solution with impurities. Do not overfill the cells and close the caps firmly to avoid leakage.
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3.4.7. Checking the transmission for leaks
Visually check that there are no apparent fluid leaks in the transmission assembly. Open the main cover to perform this check.The transmission of 1,300 and 1,600 kg capacity trucks is service free and has been filled with grease to last its entire operating life.The transmission of 2,000 kg capacity trucks is fluid-filled and serviceable. It has a filling cap at the top, a checking cap on its side and a draining cap on the underside. Check that these caps are firmly fastened. Never use your hands to check for leaks.The amount of transmission fluid is checked during semi-annual maintenance (see Section 3.7.6 Checking the amount of transmission fluid (2,000 kg capacity trucks only)).
3.4.8. Checking the condition of hydraulic tubing and couplings
Visually check the condition of all accessible hydraulic lines and couplings. Open the main cover to perform this check.The location of hydraulic components differs between truck models, but you should check that all the accessible couplings and tubing in the hydraulic system are in good condition.There should be no evidence of leaks or damage. Follow the hydraulic system from the tank and pump assembly to all couplings.
The operation of the hydraulic system is tested during daily maintenance (see Section 3.4.13 Testing the lifting hydraulics and controls).The amount of hydraulic fluid in the system is checked during weekly maintenance (see Section 3.5.3 Checking the amount of hydraulic fluid).The hydraulic fluid in the system is changed annually (see Section 3.8.1 Changing the hydraulic fluid). If you find any problems or damage in the hydraulic system, the truck must be taken out of use until it is fully operational. Refer to Chapter 5 Hydraulic operation and maintenance for information on hydraulic maintenance.
3.4.9.Testing the operation and condition of the tiller arm
When the truck is not being used, the tiller arm must rest in the upright position. Check that the arm moves smoothly between the top and bottom positions. Check that the gas spring in the tiller arm returns the arm from any position to the upright position. Check that the tiller arm is securely fastened at its base. Check for any unwanted play in the moving parts. Note that the position of the tiller arm affects driving (see Section 3.4.11 Testing the
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speed control unit, steering and the horn). If the tiller arm does not function properly or if it has sustained damage, the truck must be taken out of use until it is fully operational. Refer to Chapter 6 Mechanical maintenance for information on mechanical maintenance.
3.4.10.Testing the safety button
WARNING!
Never use a truck with a faulty safety button!
Check the operation of the safety button immediately after the main power switch is turned on.Test the operation of the safety button before continuing with the other operational tests.
Close all the covers before you switch on the main power. For the remaining daily maintenance tests, you have to switch on the truck’s main power. Refer to Chapter 2 Operating the truck for information on the truck’s controls.
The safety button is located at the far end of the tiller arm. Its purpose is to prevent the user from being crushed between the truck and a solid object.The safety button works only when moving in the direction of the tiller arm. If the button is pressed while moving, the truck should stop immediately and reverse its direction for a short time.The intensity of the reversing action is proportional to the movement speed.
Figure 3.9. Safety button
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Check the operation of the safety button by pressing it while driving the truck slowly in the direction of the tiller arm. If the safety button does not function properly, halt the maintenance process immediately and take the truck out of use until the safety button is fully operational.
Continue with this test only if the safety button of the truck is operational. Refer to Chapter 2 Operating the truck for information on the truck’s controls and driving.
1. Begin by taking hold of the tiller arm and lowering it from the upright position to the driving position. Do not lower it to the bottom position.
2. Use the accelerator on either side of the tiller arm to test the speed control. Move the accelerator gently in the forward direction.The truck should accelerate smoothly while the controller is moved. Reduce the speed from the accelerator and the truck should respond smoothly.
3. Test the reverse direction similarly. Accelerate in the forward direction once again and test reverse braking by moving the accelerator opposite to the direction of the movement.The truck should first decelerate and then begin to move in the opposite direction until the accelerator is released.
4. Test that the position sensor of the tiller arm operates by attempting to drive when the arm is in the upright and in the bottom position.The truck should not respond to the accelerator when the tiller arm is in these extreme positions.
5. Repeat the test by moving the tiller arm to the driving position, driving the truck slowly and both pressing the arm down to the bottom position and releasing it to the upright position. In both cases, the truck should stop.
6. Drive the truck both forward and backward, and test the steering by moving the tiller arm from side to side. Steering should be smooth throughout the available arc in both directions.
7. Test the horn by pressing the horn button on the tiller arm.
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If any problems are encountered during this test, take the truck out of use until it is fully operational.
3.4.12.Testing the parking brake
The trucks are equipped with an automatic parking brake.The brake should be active when the main power is off and also when the main power is on unless the accelerator is moved to issue a driving command.Test the parking brake by trying to move the truck.When the brake is active, the truck should not move forward or backward.The parking brake only affects the drive wheel so that the other wheels are still free to turn.The tiller arm can also be freely moved from side to side while the parking brake is active.
Test the operation of the lifting hydraulics by lifting and lowering the forks. Refer to Chapter 2 Operating the truck for information on the truck’s controls.The forks should rise smoothly from the lowest position to the highest position.The forks should stop smoothly when reaching the upper position. If the forks hit the upper position at full speed, there may be a problem in the system. Refer to Chapter 6 Mechanical maintenance for information on mechanical maintenance.
3.5.Weekly maintenance
Like daily maintenance, weekly maintenance is important for keeping the truck in full working order.Weekly maintenance should be scheduled for a certain day of the week, so that the maintenance interval does not fluctuate.When weekly maintenance is due, complete all of the daily maintenance procedures first before continuing with the weekly maintenance procedures.
Before beginning, ensure that the main power of the truck is turned off. Open the main and top covers of the truck before commencing with the weekly maintenance procedures. Refer to Section 3.2 Maintenance guidelines for information on how to open the truck’s covers.
Should the weekly maintenance procedures reveal anything that affects the use or safety of the truck, the truck must immediately be taken out of use until it is restored to full working order.
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3.5.1. Checking that fixing hardware and tube couplings are secure
Check that all accessible fixing hardware is securely fastened, and that there is no play between parts that should be firmly fixed. Check that all the couplings in the hydraulic system are tight.
3.5.2. Checking and cleaning the batteries and battery cabling
The batteries of the 1,300 kg capacity truck are located in the main chassis, so you have to open the main cover to access them.The batteries of the 1,600 and 2,000 kg capacity trucks are located in the battery compartment between the main chassis and the forks. Open the battery compartment cover to access the batteries.
Visually check the condition of the two batteries on 1,300 kg capacity trucks.Visually check the condition of the battery cells on 1,600 and 2,000 kg capacity trucks. Check that all the battery cabling (both to the main poles and between cells) is securely fixed and in good condition, with all the insulators intact.
Over time, grime accumulates onto the batteries. Clean batteries weekly with a non-conductive and non-abrasive dry cloth. Never use water or any other cleaning agent when cleaning batteries or battery cells.Take precautions for handling lead-acid batteries, which contain a corrosive acid solution.Take care to not short-circuit a battery or cell connection.
3.5.3. Checking the amount of hydraulic fluid
Check the amount of fluid in the hydraulic system. Before checking the amount, ensure that there is no pressure in the system, that is, that the forks are resting in the lowest position. The location of the hydraulic tank differs between truck models, but it is visible when the main cover is open. On 1,300 kg capacity truck models, the tank is installed horizontally, and it should be half full.
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Figure 3.10. Hydraulic tank location (1,300 kg capacity truck model)
On 1,600 kg and 2,000 kg capacity truck models, the tank is installed vertically, and it should be filled to three-quarters (¾) of the capacity when measured from the bottom of the tank to the bottom edge of the filling tube.
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Figure 3.11. Hydraulic tank location (1,600 and 2,000 kg capacity truck models)
If the level of fluid in the tank is below the above amounts, you must add hydraulic fluid to the system. Refer to Section 3.9 Lubricant and fluid recommendations for fluid recommendations. When adding hydraulic fluid to the system, use only new and clean fluid, and uphold cleanliness during the operation so that contaminants are not introduced into the hydraulic system.Take appropriate precautions when handling hydraulic fluid, as it is harmful.
3.5.4. Checking the condition of identification plates and labelling
The main identification plate of the truck is located on the underside of the tiller arm. Check that it is firmly in place, undamaged and fully legible. If the plate is missing or cannot be read, a new one must be fitted. In addition to the identification plate, check that other labelling and markings, such as lifting points or any warnings, are in place and intact.
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3.5.5. Cleaning the truck
Clean the truck at least once a week. Keeping the truck clean upholds safety and helps to maintain it in good working condition. If the truck is kept clean, it is also easier to notice possible damage or wear.
When cleaning the truck, take care not to let water or other fluids enter the main chassis or battery compartment. Never use a pressure washer to clean the truck. Use a dry and clean cloth when possible and use solvents only when necessary. If solvents are necessary, make sure that the chemicals will not harm the surface or component that is being cleaned.
3.6. Monthly maintenance
There is only one monthly maintenance procedure, which affects 2,000 kg capacity trucks.
3.6.1. Lubricating the drive unit bearings (2,000 kg capacity trucks only)
The bearings of the drive unit must be lubricated monthly. Open the main cover of the truck to gain access to the bearing.The bearing assembly to be lubricated sits above the drive motor and transmission assembly.The lubrication nipple should be used to lubricate the bearings.
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Figure 3.12. Lubrication nipple location
Use a grease gun to press the lubricant into the bearing assembly. Refer to Section 3.9 Lubricant and fluid recommendations for lubricant recommendations. After lubrication, move the tiller arm from side to side to distribute the lubricant evenly in the bearing assembly.
3.7. Semi-annual maintenance (after 600 hours of operation)
Semi-annual maintenance should be carried out either after half a year or after 600 hours of use, whichever is sooner. If the truck is equipped with an operating time meter, semi-annual maintenance is easy to schedule. If not, the operating time can be read using the console (refer to Chapter 4 Electrical operation and maintenance for more information on using the console). The semi-annual maintenance procedures should be carried out only by a trained professional.
3.7.1. Daily and weekly maintenance procedures
Before beginning the semi-annual maintenance procedures, both the daily and weekly maintenance procedures must be carried out as explained above.
Before continuing to the semi-annual maintenance procedures, ensure that the power to the truck is turned off.The procedures
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described below require that you first remove the main and top covers of the truck.
Visually check that all the main electrical connections and cabling of the truck from the battery to the drive and pump motors are in good working order.Take appropriate precautions for performing electrical maintenance.
1. Begin by checking that the main battery connection is firmly in place.
Figure 3.13. Main battery connection (1,300 kg capacity truck model)
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Figure 3.14. Main battery connection (1,600 and 2,000 kg capacity truck models)
2. Follow the main cabling from the battery connection to the main fuses.Visually check the condition of the cabling for any damage. One fuse routes power to the drive motor while the other routes power to the pump motor.
3. Check that all the connections to and from the fuses are secure and that the cable ends are in good working order.
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Figure 3.15. Main fuses
4. Follow the power cable to the traction controller.Visually check that the cable is in good working order.
5. Check that all the traction controller connections are secure and that the cable ends are in good working order.
Figure 3.16.Traction controller
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6. Follow the three phases cables from the traction controller to the drive motor while checking the condition of the cables.
Figure 3.17.Traction motor connections
7. Return to the main fuses and follow the power cable to the pump contactor.Visually check that the cable is in good working order.
8. Check that the contactor connections are secure and in good working order.
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Figure 3.18. Pump contactor
9. Follow the cabling from the pump contactor to the pump motor and check the condition of the cables.
Figure 3.19. Pump motor connection
10.Check the security and condition of the main minus connection and all the cabling attached to it.
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Figure 3.20. Universal minus connection
After these main connections have been checked, continue by visually checking the condition of the remaining accessible electrical cabling and connections. Pay special attention to binding points and eyelets, as well as other locations where cables or cable groups are or may come under stress during use.
As the forks are the working part of a truck, they wear and may become damaged during use. It is necessary to monitor their condition regularly. Ordinary wear, such as that of the paint or surface, is acceptable, but any actual damage or deformation of the forks must be fixed before the truck is returned to use.
Verify that the forks are straight and parallel to each other. Check that they do not droop, and that they are at right angles to the main chassis both vertically and horizontally. Also check that they do not hang between the supporting points, that is, the main chassis and the load wheels. A hang of up to 10 mm is acceptable.
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Figure 3.21. Checking the forks
3.7.4. Checking, cleaning and adjusting the brake
Check the brake for wear and clean it.The brake on 1,300 and 1,600 kg capacity trucks cannot be adjusted, and the brake pad must be replaced when it has worn.The air gap in the brake of the 2,000 kg capacity truck can be adjusted to compensate for the wear of the brake pad.
Open the main cover to perform these maintenance procedures. Turn the tiller arm so that you can access the brake. Remember to uphold a clean working environment when working with the brake so that you do not inadvertently introduce dirt into the brake mechanism.
3.7.4.1. 1,300 and 1,600 kg capacity trucks
Check the wear of the brake pad and clean the brake. Perform the following procedure to service the brake.
1. Open the three screws that fix the brake to the drive unit.
Use a 7 mm wrench.
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Figure 3.22. Brake fixing screws
2. Detach the brake unit carefully.
3. Detach the brake pad and measure its thickness.The thickness of a new brake pad is 7.6 mm. Replace the pad when it has worn to a thickness of under 7.4 mm.
Figure 3.23. Checking the brake pad thickness
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4. After checking/replacing the brake pad, clean the brake unit from any accumulated dust with pressurised air. Follow work safety procedures when using pressurised air and use a low pressure.
5. After the above procedures, reattach the brake unit to the drive unit.
3.7.4.2. 2,000 kg capacity trucks
Check the wear of the brake pad by measuring the air gap. If the air gap is within acceptable limits, only cleaning the brake with pressurised air is necessary.
To service the brake:
1. Remove the rubber gasket over the brake air gap.
Figure 3.24. Removing the rubber gasket
2. Use a feeler gauge to measure the air gap of the brake.
Measure the air gap at three points near each fixing screw.
The air gap should be between 0.2 and 0.55 mm and equal at each point.The air gap increases as the brake pad wears.
If the air gap is within limits and equal at each point, continue directly to Step 5. Otherwise, continue to Step 3.
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52 3. To adjust the air gap, loosen the three fixing screws with a 7 mm wrench and adjust the gap with the adjustment nuts in the brake. Retighten the fixing screws and measure that the air gap is within limits and equal at each point. Repeat this procedure if necessary to set the air gap as near 0.2 mm as possible to allow for wear. If the adjustment is successful, continue directly to Step 5, otherwise continue to Step 4.
Figure 3.25. Adjusting the air gap
4. If the brake pad has worn so much that the air gap can no longer be adjusted, the pad should be replaced. If the pad must be replaced, open the brake completely, remove the old brake pad and replace it with a new brake pad.The thickness of a new brake pad should be 8.5 mm.
Reassemble the brake after replacing the brake pad and return to Step 3.
5. After the brake has been checked and possibly serviced, it must be cleaned. Use pressurised air to remove any accumulated dust from the brake. Follow work safety procedures when using pressurised air and always use a low pressure.
6. After the above steps, reattach the rubber gasket. Carefully position the gasket so that its skirt falls into the grooves on both sides to seal the enclosure.
3.7.5. Checking the fastening of the transmission and the drive unit (2,000 kg capacity trucks only)
Check that the drive unit fixing bolts and the main transmission bolts are securely fastened.
Figure 3.26. Main transmission bolts
Figure 3.27. Drive unit fixing bolts
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For this check, access the checking hole on the side of the transmission unit. If you need to lift the truck to perform the check, make sure that it remains level while performing this check. Remember cleanliness and follow fluid safety procedures.
To check the fluid level, open the cap of the checking hole with a 5 mm Allen key. If the fluid level is clearly lower than the edge of the checking hole, you must add transmission fluid. For more information on adding transmission fluid, refer to Section 3.8.2 Changing the transmission fluid (2,000 kg capacity trucks only). Refer to Section 3.9 Lubricant and fluid recommendations for fluid recommendations.
Figure 3.28. Location of the checking hole
3.8. Annual maintenance (after 1,200 hours of operation)
Annual maintenance should be carried out either after a year or after 1,200 hours of use, whichever is sooner. If the truck is equipped with an operating time meter, annual maintenance is easy to schedule. If not, the operating time can be read using the console. Refer to Chapter 4 Electrical operation and maintenance for more information on using the console.The
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annual maintenance procedures should be carried out only by a trained professional.
3.8.1. Changing the hydraulic fluid
The hydraulic fluid must be changed once a year on all truck models.The location of the hydraulic system components differs between truck models. Follow the given instructions based on the truck model. Note that the filling cap functions as a breather for the tank, so do not overtighten it or overfill the tank to avoid leakage. Refer to Section 3.9 Lubricant and fluid recommendations for fluid recommendations. Remember cleanliness and follow the precautions for handling harmful fluids.
3.8.1.1. 1,300 kg capacity trucks
Remove the main and top covers of the truck.The hydraulic pump and tank assembly is located in the upper left part of the main chassis when viewed from the front.The assembly is installed horizontally.
To drain the fluid from the tank, use a draining apparatus. Make sure that all the tools and tubing you use are clean so that no dirt is introduced into the hydraulic system. After draining the tank completely, fill it to half (½) its volume with new hydraulic fluid.
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Figure 3.29. Draining the hydraulic tank (1,300 kg capacity truck model)
3.8.1.2. 1,600 kg capacity trucks
Remove the main and top covers of the truck.The hydraulic pump and tank assembly is installed vertically.The filling tube of the tank has a right angle, so the tank must be removed to drain the old fluid. Remove the hydraulic tank according to the following steps.
1. The hydraulic pump and tank assembly is fixed to a bracket, which is fixed to the bottom of the main chassis. Locate the bolts that fix the bracket to the chassis and open them.
2. After opening the bolts, turn the assembly out of the chassis to gain access to it.
3. Open the four screws that hold the entire assembly together using a 4 mm Allen key. Be careful when handling the assembly with the screws removed.
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Figure 3.30. Removing the hydraulic tank (1,600 kg capacity truck model)
4. Carefully remove the tank and pour out the old hydraulic fluid.
5. Reattach the tank to the rest of the assembly and refix the four fixing screws.
6. Reattach the entire assembly to the main chassis.
7. Open the filling cap and fill the tank with new hydraulic fluid to three-quarters (¾) of its capacity when measured from the bottom of the tank to the filling tube.
3.8.1.3. 2,000 kg capacity trucks
On 2,000 kg capacity trucks, you have to remove the battery pack to gain access to the fixing screws that hold the hydraulic pump and tank assembly. Except for the hydraulic pump and tank assembly being fixed directly to the back plate of the main chassis, the process is similar to the 1,600 kg capacity truck model.
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Take the utmost care and suitable precautions when lifting the battery assembly from the truck. Protect any unshielded contacts against short-circuiting. Use a non-conductive belt for hoisting the battery assembly.The battery assembly can be lifted with a crane or another truck.
Figure 3.31. Removing the battery pack (2,000 kg capacity truck model)
After the battery assembly has been removed, you can access the fixing screws for the hydraulic pump and tank assembly. Follow the procedure given for the 1,600 kg capacity truck for draining and refilling the tank. After the pump and tank assembly has been reattached, replace the battery assembly.
3.8.2. Changing the transmission fluid (2,000 kg capacity trucks only)
Change the transmission fluid once a year on 2,000 kg capacity trucks.The transmission has three orifices: the filling hole (1) at the top, the checking hole (2) on the side, and the draining hole (3) on the underside.
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NOTE
Figure 3.32. Location of filling (1), checking (2) and draining (3) orifices
The filling cap is opened with a 12 mm wrench, while the checking and draining hole caps require a 5 mm Allen key.Take precautions for handling transmission fluid and keep the servicing area clean.
To change the transmission fluid:
1. Lift the truck with a suitable jack or other safe method and secure it to a level position. Always secure the truck so that it is safe to work under. Never work under a truck that is supported only by jacks.
2. After the truck has been lifted and levelled, place a suitable container under the transmission draining hole.There is approximately 0.6 litres of fluid in the transmission.
3. Open the draining hole cap using a 5 mm Allen key.
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60 Figure 3.33. Opening the draining cap
4. Open the filling hole cap using a 12 mm wrench and let the transmission fluid drain completely.
Figure 3.34. Opening the filling cap
5. Close the draining hole cap.
6. Open the checking hole cap using a 5 mm Allen key.
Figure 3.35. Location of the checking hole
7. Using a funnel, pour new transmission fluid carefully into the filling hole until it reaches the level of the checking hole.
Refer to Section 3.9 Lubricant and fluid recommendations for fluid recommendations.
8. Close the checking and filling hole caps.
3.9. Lubricant and fluid recommendations
Take the appropriate precautions when handling lubricants and fluids during maintenance. Many of the used fluids are harmful or even toxic, and some solutions are corrosive. Always use protective clothing, eyewear and gloves when handling harmful fluids. Refer and conform to all local safety guidelines governing these fluids and lubricants. Before use, always familiarise yourself with a substance by reading the instructions and precautions for use from the container or associated documentation. Never handle an open flame or smoke a cigarette in or near the area where these substances are handled.
3.9.1. General lubricant
Use grease that conforms to NLGI grade No. 2 requirements as the general lubricant for moving parts in trucks. If the truck is used in cold environments, such as cold store applications, use NLGI No. 1 or No. 0.
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3.9.2. Battery fluid
Use fluid intended for lead-acid batteries as the battery fluid for trucks with serviceable batteries. Never use any other fluid to fill the battery cells.
3.9.3. Hydraulic fluid
Normally use fluid of the ISO VG 32 viscosity class as the hydraulic fluid. Use fluid of the ISO VG 15 viscosity class in cold environments.
3.9.4.Transmission fluid
The transmissions of 1,300 and 1,600 kg capacity trucks are grease filled at the factory and do not require service. Use transmission fluid of grade EP 80 or 90 as the transmission fluid for 2,000 kg capacity trucks.
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4. Electrical operation and maintenance
This chapter examines the electrical aspects of the truck.The chapter begins with a description of the truck's electrical operation. It continues by introducing the console and presents its use in reading and modifying controller parameters.The chapter concludes with electrical maintenance and repair instructions not covered in Chapter 3 Regular maintenance.
Refer to Section 3.1 Safety guidelines and preparation and Section 3.2 Maintenance guidelines for information on safety and preparation for maintenance tasks. Refer to Chapter 2 Operating the truck for operating instructions.
4.1. Electrical operation
This section presents the truck's primary electrical functions. Ensure that you have the correct version of the electrical schematics for the truck model under maintenance. Contact your supplier or technical support for information on obtaining up-to-date documentation for your truck.
The section assumes that you are using the standard model of the truck.This chapter only addresses the primary electrical functions.To troubleshoot a particular component, you need to locate it on the electrical schematic diagram to understand how it is connected to the entire system. Keep a copy of the electrical schematic diagram at hand while reading this chapter.
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4.1.1. Using the schematic diagram
NOTE
Figure 4.1. A sample page from the electrical schematic diagram of the pedestrian power pallet truck (TS980803)
Always acquire the correct version of the electrical schematics before proceeding with electrical maintenance.
The electrical schematic diagram is divided into zones, which are presented along the top edge of each page. Use these zones
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as a navigating aid to locate components. For example, the text may refer to a component in a certain zone of a certain page of the schematics.
4.1.2. Power source
The electrical power source differs between truck models.Trucks with a nominal lifting capacity of 1,300 kg use two 12-volt batteries.These batteries are either AGM type batteries with a maximum capacity of 35 Ah or GEL type batteries with a maximum capacity of 48 Ah.The batteries are presented in zone 11 of page 1 of the electrical schematic diagram.They are marked G1 and G2 and are connected in series to provide the system with the required 24 volts.
The more powerful truck models with nominal lifting capacities of 1,600 and 2,000 kg have wet lead-acid batteries, which consist of 12 cells and supply a nominal voltage of 24 volts.The batteries have a maximum capacity of 270 Ah on the 1,600 kg capacity truck model and 345 Ah on the 2,000 kg capacity truck model. The batteries reside in a separate compartment and are connected to the system via the XG1 battery connector.The battery is presented as G1 in zone 13 on page 1 of the electrical schematic diagram.
4.1.3. Key switch
The main key switch S1 controls the electrical power supply to the entire system. It also functions as the emergency stop button. The main key switch is activated by pulling it up, which closes the switch. If the system needs to be powered down at any time, the key switch can be pressed.This opens the S1 switch connection.The switch is located in zone 13 on page 1 of the electrical schematic diagram.
When the main key switch closes the contact, electrical power is supplied to the system through the main fuses 1F1 and 2F1. Fuse 1F1 supplies the battery positive voltage B+ to the traction controller.The fuse is rated at 70 A on 1,300 and 1,600 kg capacity trucks, and 100 A on 2,000 kg capacity trucks. Fuse 2F1 supplies B+ to the pump motor contactor K1.The fuse is rated at 70 A on all the truck models. Refer to the electrical schematic diagram for the location of the main fuses in zones 13 and 15 on page 1.
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After the main fuse 1F1, the B+ supply is fed to the main positive input terminal of the traction controller.The positive power feed is internally connected to the auxiliary fuse A1F1 in the traction controller. Fuse A1F1 is rated at 5 A. Refer to zone 20 on page 1 of the electrical schematic diagram. On 2,000 kg capacity trucks, the main positive electrical power feed is also connected to pin 1 of connector X1 of the traction controller.The battery negative pole B- is connected directly to the negative input terminal of the traction controller.
The pump motor contactor K1, which is fed through the main fuse 2F1, is controlled by the traction controller. In the schematic diagram, the K1 contacts are presented in zone 15 on page 1. The coil controlling the K1 contacts is presented in zone 23 on page 1.The coil is connected to pins 5 and 10 of connector X3 of the traction controller. Pin X3:5 is the positive supply and pin X3:10 is the digital output for the pump motor contactor.The contactor coil is powered as long as the battery voltage is high enough. Lifting is disabled when the battery voltage drops under the level set with the Level low batt. parameter of the traction controller. Refer to Section 4.2 Console for information on reading and modifying the parameters of the traction controller.
4.1.4.Traction
The movement of the truck is controlled by the traction controller. Before the truck can be driven, the battery must be connected, the main key switch must be closed (in the up position) and the system must have passed the self-test procedure.
When the truck is powered on and in standby mode, it can be driven by moving the accelerator at the end of the tiller arm towards the forward or backward direction.The accelerator is presented in zones 23 to 26 on page 1 of the electrical schematic diagram. Refer to Chapter 2 Operating the truck for more information on driving the truck.
The accelerator unit receives its 24-volt electrical supply from pin 1 of connector X6.The negative connection is supplied through pin 7 of connector X6. As the accelerator is moved in either direction, it indicates the direction to the traction controller via pins 2 and 3 of connector X6. It also provides a varying voltage to pin 6 of connector X6.The voltage varies between approximately 0.3 and 5 V, and depends on the position of the
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NOTE
accelerator control.The voltage increases as the accelerator is moved to either extreme. If the accelerator needs to be replaced for any reason, the sensor values should be reread using the console. Refer to Section 4.3.2.38 Parameter 251: Program throttle for information on the Program throttle parameter.
When the voltage at pin 6 of connector X6 of the traction controller rises above 0.3 V, the controller first checks the directional inputs (pins 2 and 3 of connector X6) for a direction indication.The controller also checks for any internal errors. Before the controller engages the traction motor, it releases the 1Y1 electrical parking brake.
The brake is controlled through pins 1 and 5 of connector X4. The parking brake is active when it receives no power, that is, also when the truck is powered down.To release the brake, the traction controller applies 24 V to pin 1 of connector X4 for one second and then reduces the voltage to 60% to hold the brake open. Refer to zone 18 on page 1 of the electrical schematic diagram.
After the parking brake is released, the traction controller begins to feed the three-phase alternating current to drive the M1 traction motor.The AC traction motor is connected to the U, V and W outputs of the traction controller. Refer to zones 17 to 19 on page 1 of the electrical schematic diagram.
Figure 4.2.Traction motor connections
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NOTE
The truck is powered by a DC battery.The direct current is converted in the traction controller to three-phase alternating current to drive the AC traction motor.This process is known as inverting.The three motor inputs are driven out of phase to create a voltage drop between the phases.The order of the phases, that is, which phase is leading and which phases follow, determines the rotating direction of the motor.
The rotating speed of the motor is relational to the width and frequency of the pulse.The greater the pulse width, the longer current flows through the motor.The actual current passing through the motor is more sinusoidal than pulsed due to the characteristics of an inductor.The pulse width varies depending on feedback from the traction speed encoder bearing B3. If the motor revolves faster than the speed reference, the pulse width is decreased and vice versa.
Motor speed feedback allows the control system to maintain an exact speed, regardless of the load on the truck.The feedback process continues until the request to move ends. In other words, until you release the accelerator or an alarm occurs, which forces the traction controller to cease operation and to engage the brake. If there are no alarms when the accelerator is released, the traction controller reverses the motor phasing to slow it down (by attempting to reverse its rotating direction).The parking brake is engaged once the motor has stopped revolving, which the traction controller senses via the traction speed encoder. The maximum forward and backward travel speeds of the truck can be modified with the console.The maximum permitted speed of a pedestrian truck is 6 km/h. Refer to Section 4.2 Console for more information on using the console to adjust parameters.
The traction speed encoder is connected to the traction controller at pins 3, 4, 7 and 8 of connector X4. Pin 7 supplies the encoder with 15 volts while pin 8 supplies the negative connection. Pin 3 is encoder channel A and pin 4 is encoder channel B.
The traction controller determines the rotating speed of the motor by counting the pulses produced by the encoder over a certain period.The faster the motor turns, the more pulses are generated during the monitoring period.The rotating direction of the traction motor is determined by comparing the signals of the two channels.The motor’s turning direction causes the signal of one channel to lead while the other lags.
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NOTE
The operation of the traction speed encoder can be tested using the console. Refer to Section 4.2 Console for more information on using the console.
4.1.5. Braking
NOTE
The truck is normally slowed down with the traction motor.When the truck is being driven in one direction, reducing the deflection of the accelerator control causes the system to reduce the speed reference to the traction motor, which actively reduces the speed. The operator can slow down the truck more rapidly by turning the accelerator in the opposite direction to the movement.This causes the traction controller to instruct the traction motor to reverse its movement and therefore to rapidly reduce its turning speed. If the accelerator is held in this position after the truck has stopped, it begins to move in the given direction at the requested speed.
In practice, when the accelerator is turned opposite to the direction of movement, the traction controller switches the order of the two of the three motor input phases (U, V and W).This action forces the traction motor to reverse its rotating direction. This will initially slow down the motor and then begin to turn it in the opposite direction. Braking characteristics can be adjusted with the Reverse braking parameter. Refer to Section 4.2 Console and Section 4.3.2 Parameters for more information on setting truck parameters with the console.
When the movement of the truck is slowed down with the motor, the motor acts as a generator and produces electrical power. This power is used to recharge the truck’s battery.This is known as regenerative or inverse braking. In this situation, the motor produces AC voltage from each of its phases.This AC voltage is rectified to a direct positive and negative voltage. As long as the resultant DC voltage is higher than the battery voltage, the battery is charged.
The truck is equipped with an electrical brake, but this is normally not used to control the truck’s speed.The Stop mode tiller parameter controls the function of the electrical brake. In the default mode, the electrical brake is engaged only after the truck's movement has stopped.This reduces the wear on the electrical brake.The electrical brake can be used to slow down the truck, but this is not recommended.
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4.1.6. Safety button
The truck is by regulations obligated to have a safety button to protect the operator.The safety button is situated at the far end of the tiller arm. Its purpose is to stop and reverse the direction of the truck’s movement to minimise the risk of the operator being crushed between the truck and an obstacle.
The safety button works only when the truck is driven in the direction of the tiller arm.When the button is pressed, the truck automatically stops and reverses its movement for a short period. The sharpness of the response is controlled by parameter 142 and also by the original speed.The response is greater at faster driving speeds. Refer to Section 4.2 Console for more information on setting the truck’s parameters with the console.
The safety button S2 is located in zone 23 on page 1 of the electrical schematic diagram.When it is pressed, it opens the connection and removes the 24-volt electrical supply from pin 4 of connector X6.This causes the controller to connect the reverse direction.The reversing acceleration is set with parameter 142.
4.1.7. Lifting and lowering the forks
The forks are lifted hydraulically.The operator requests lifting or lowering by using the micro switches in the tiller arm head. Lifting is requested with switch S4 and lowering with switch S5. Refer to zones 28 and 29 on page 1 of the electrical schematic diagram.
When the operator requests lifting, switch S4 is closed, which sends the 24-volt signal to pin 8 of connector X6 of the traction controller. Before the traction controller reacts to the request, the battery voltage must be above a designated level.The traction controller energises the K1 contactor coil through pin 5 of connector X3. K1 closes and feeds the battery voltage to the pump motor.The pump motor engages and turns the pump to draw hydraulic fluid from the tank and send it to the lifting cylinder. The pump motor runs until the lifting request is removed or the forks reach the top position.When the top position is reached, the lifting limit switch (S7) opens, which deactivates the pump motor.
When the operator requests lowering, switch S5 is closed, which sends the 24-volt signal to pin 9 of connector X6.The traction controller then controls the magnetic valve through pin 4 of
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connector X3. Refer to Chapter 5 Hydraulic operation and maintenance for information on the hydraulic operation of the power pallet truck.
4.2. Console
The handheld console provides a user interface to the controllers used in trucks.The console can be used to verify the operation of the truck, read and modify controller parameter values, monitor the inputs and outputs of a controller, and display the error code when a fault has occurred.The console used in conjunction with these trucks is the BPK part number (RL)469054. Contact your supplier for information on obtaining a handheld console.
Figure 4.3. Handheld console, model BPK ((RL)469054)
4.2.1. Connecting the console
Before connecting the console, make sure that the truck’s main key switch is turned off.The console is connected to connector X7 of a controller.To access the connector, remove the main cover of the truck. Refer to Chapter 3 Regular maintenance for information on removing the truck’s covers.The connector may already be reserved by a peripheral device, such as a display unit. If so, simply disconnect the peripheral device to connect the console, and reconnect the peripheral device after disconnecting the console.
To connect the console:
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1. Turn off the truck’s main key switch.
2. Open the main cover and locate the controller.
3. Disconnect a possible peripheral device (e.g. the display unit) from controller connector X7.
4. Connect the connection cable of the handheld console to connector X7 on the controller.
4.2.2. Navigating the parameter list
After the console is connected to the controller, the truck’s main key switch can be turned on. As the console goes through its start-up procedure, it first displays its own software version. After the start-up sequence, the console displays the serial number and software version of the controller to which it is connected.
The handheld console has six keys on its face: four arrow keys, an Esc key and an Enter key. Use the up and down arrows to scroll through the available parameters.
Press the down arrow from the first display to scroll to the first available parameter.The console displays “Searching next parameter” for a short period, then the name and number of the parameter, before displaying the name and value of the parameter.
Some controller parameters are diagnostic parameters and cannot be modified by the user.When you reach a modifiable parameter, press the left or right arrow key to enter editing mode. After the cursor has appeared, move it to the correct position with the left and right arrow keys and modify the selected value with the up and down arrow keys.
When in editing mode, if a value is changed and no keys are pressed for one second, the new value is temporarily in use but has not been stored into the system.The Enter key must be pressed to store the value in the controller memory and to exit editing mode. If you wish to discard any changes and return to the previous stored value, press the Esc key to exit editing mode without storing the new value.
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4.2.3. Accessing additional functions
The handheld console provides additional functions, which can be accessed by pressing the left and right arrow keys simultaneously.This opens a submenu with the following choices:
List of errors
This function displays a chronological list of the last eight controller faults that have occurred.The eight slots are reserved for different fault codes. If the same fault has occurred several times, it is displayed only once.
Write (BPK->dACi) and Read (dACi->BPK)
These commands are used to upload and download parameter sets to a controller.This can be useful, for example, when the controller must be replaced and settings must be moved to the new controller, or when several controllers are to be programmed with the same parameter set.
The Read (dACi->BPK) command is used to read and store the parameter values of a connected controller into the BPK handheld console.The handheld console has memory space to store up to eight parameter sets.When using this command, you are asked to select one of the available storage locations.
The Write (BPK->dACi) command is used to overwrite the parameter set of a connected controller. Once this function is selected, the console asks you to select one of the eight possible parameter sets to be downloaded to the controller. Be careful with this command, as it overwrites the entire parameter set of the connected controller.
Search device
When the connected controller is on a communication bus that contains other controllers, this function can be used to search for the device addresses of the controllers on the bus.
Select address
When the connected controller is on a communication bus that contains other controllers, this function can be used to connect the console to a different controller on the same bus.
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Select language
Use this function to select one of the two available console user interface languages: English or German.
4.3.Traction controller
The traction controller is an important part of the truck’s electrical system. Depending on the truck model, it controls some or nearly all the electrical functions, such as driving, braking, lifting and lowering the forks, and the safety functions.The main task of the traction controller is to act as an inverter and convert the DC battery voltage to AC electrical power to drive the AC electrical motor.
4.3.1. Connections
As the electrical schematic diagram shows, the traction controller is connected to several electrical components of the truck.The traction controller A1 is presented in zones 20 to 22 on page 1 of the electrical schematic diagram.There are different models of the controller for different truck models.They, however, all function similarly. If the controller has to be replaced, contact your supplier or technical support for information on obtaining up-to-date documentation and parts for your truck.
Figure 4.4.Traction controller
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NOTE
The traction controller has two main DC voltage inputs from the battery. It has three main AC voltage outputs to the three phases of the traction motor. In addition to these connections, the controller has several connectors for peripheral devices.The different connectors of the traction controller are listed below. Refer to the given sections of the electrical schematic diagram to locate the connectors.The actual physical location of the connectors on the traction controller varies by model, but is marked on its casing. The operation of the traction controller connections can be tested with the console. For more information, refer to Section 4.2 Console and Section 4.3.2 Parameters.
4.3.1.1. Connector X1 (zone 20, page 1)
X1, pin 1:The battery voltage is applied to this input in order to power on the controller.The input is protected by a 5 A fuse, which can be reached from outside the controller housing.This input provides the voltage supply for the other peripheral components.
Pins 2, 3 and 4 of connector X1 are not in use. Do not connect.
4.3.1.2. Connector X2 (zone 12, page 2)
This connector is not used in this application. Do not connect.
4.3.1.3. Connector X3 (zones 21-22, page 1)
X3, pin 1:This pin supplies the 24-volt battery voltage to the safety socket switch S8 (zone 28, page 1). If the charging plug is removed from its socket, traction is disabled. Lifting is still permitted.
X3, pin 2:This pin supplies the 24-volt battery voltage to the lifting limit switch S7 (zone 27, page 1).When the lifting limit of the forks is reached, this switch opens and disables lifting.
X3, pin 3:The positive voltage supply for the H2 horn (zone 25, page 1).This output is controlled by input X6:10.
X3, pin 4:The positive voltage supply for the magnetic lowering valve 2Y1 (zone 24, page 1).This output is controlled by input X6:9.
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X3, pin 5:The positive voltage supply for the K1 pump motor contactor (zone 23, page 1).This output is controlled by input X6:8.
X3, pin 6:The digital input for the safety socket switch S8. See X3, pin 1.
X3, pin 7:The digital input for the lifting limit switch S7. See X3, pin 2.
X3, pin 8:The negative connection for the horn H2.
X3, pin 9:The negative connection for the magnetic lowering valve 2Y1.
X3, pin 10:The digital output for the K1 pump motor contactor.
4.3.1.4. Connector X4 (zone 20, page 1)
X4, pin 1:The positive 24-volt supply for the 1Y1 electrical brake (zone 18, page 1).
X4, pins 2 and 6: Connection for the motor temperature sensor. Not used in this application. Do not connect.
X4, pin 3: Channel A signal link from the B3 motor encoder (zone 17, page 1).
X4, pin 4: Channel B signal link from the B3 motor encoder.
X4, pin 5: Digital output for the 1Y1 electrical brake.
X4, pin 7:The 15-volt supply for the B3 motor encoder.
X4, pin 8:The 0-volt connection for the B3 motor encoder.
4.3.1.5. Connection X5 (zone 20, page 1)
X5, pin 1:The positive 24-volt supply for the H1 status LED (zones 16-17, page 1).
X5, pin 2:The positive 24-volt supply for the B2 tiller arm position switch (zones 17-18, page 1).
X5, pin 3: Input from the tiller arm position switch. Indicates that the tiller arm is in the driving position.
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X5, pin 4: Digital output for the H1 status LED.
X5, pin 5:The 0-volt connection for the B2 tiller arm position switch.
X5, pin 6: Input from the tiller arm position switch. Indicates that the tiller arm is either in the upright or in the bottom position. In these positions, traction is disabled unless the S3 brake release switch is closed.
4.3.1.6. Connector X6 (zones 21-22, page 1)
X6, pin 1:The positive 24-volt supply for the B1 tiller arm head module (zones 23-30, page 1).
X6, pin 2: Digital input from the accelerator for the forward direction.
X6, pin 3: Digital input from the accelerator for the backward direction.
X6, pin 4: Digital input from the safety button (S2) (zone 23, page 1). Switch S2 is normally closed. If S2 is opened, the 24-volt supply is removed from this terminal and the traction controller acts accordingly.
X6, pin 5: Digital input from the brake release switch S3 (zone 28, page 1). By pressing this switch, the operator can drive the truck at reduced speed even when the tiller arm is in the upright or bottom position.
X6, pin 6:The speed reference input from the accelerator.
X6, pin 7:The battery negative connection for the B1 tiller arm head module.
X6, pin 8: Input for the lifting switch S4 (zone 28, page 1). Controls the X3:5 output.
X6, pin 9: Input for the lowering switch S5 (zone 29, page 1). Controls the X3:4 output.
X6, pin 10: Input for the horn switch S6 (zone 29, page 1). Controls the X3:3 output.
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X6, pin 11: 10-volt output, 100 mA maximum current. Not connected.
X6, pin 12: Digital input for speed reduction. Not in use. Connected directly to pin 1.
4.3.1.7. Connector X7 (zone 12, page 2)
This is the controller’s RS485 interface connector. If the truck is equipped with a display unit, it is connected to connector X7. The console connects to this connector. If a display unit is included, it must be disconnected before the console is connected. Refer to Section 4.2 Console for more information on using the console.
X7, pin 1: 15-volt supply.
X7, pin 2: 0-volt connection.
X7, pin 3: RS485, signal A.
X7, pin 4: RS485, signal B.
4.3.2. Parameters
There are two main parameter types in the controller: diagnostic and modifiable.The values of diagnostic parameters can be viewed but cannot be changed.The parameters available for the traction controller are presented below.Their order is determined by the parameter number, which controls the order in which they are listed on the handheld console.
You may notice that not every parameter is available even for viewing.The console shows only those parameters that are meant to be user read or modified. Other parameters exist, but these are either not used in the current application or they have been preset by the manufacturer. Do not alter the value of a parameter unless you are completely certain of the necessity of the change and aware of how it affects the truck’s operation.
NOTE
This parameter displays the version of the connected controller’s internal software.
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This parameter displays the operating time of the connected controller.The time is displayed in hours and to an accuracy of three decimals.
4.3.2.3. Parameter 7: Serial number (diagnostic)
This parameter displays the serial number of the connected controller.
4.3.2.4. Parameter 10: Actual speed (diagnostic)
This parameter displays the actual current speed of the truck in km/h.
This parameter displays the speed reference value from the accelerator in km/h.
This parameter displays the temperature measured from the traction controller heat sink.The temperature is displayed in degrees Celsius (°C) and to an accuracy of one degree.
4.3.2.7. Parameter 18: Battery level (diagnostic)
This parameter displays the level of the battery charge.The level is displayed as a value between 1 and 10, with 1 indicating a level of 10% and 10 indicating 100%.
4.3.2.8. Parameter 30:Throttle value (diagnostic)
This parameter displays the speed reference value from the accelerator.The value is displayed as a voltage between 0 and 5 V, and to an accuracy of one decimal.When the accelerator is in the neutral position, the value should be close to 0 V.When the accelerator is moved to either extreme, the value should increase linearly close to 5 V.
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This parameter displays the current measured battery voltage. The nominal voltage in this application is 24 V.The reading decreases while the truck is operated, as electrical power is drawn from the battery.
4.3.2.10. Parameter 46: Connector X1 (diagnostic)
This parameter displays the active pins of connector X1.
4.3.2.11. Parameter 47: Connector X2 (diagnostic)
This parameter displays the active pins of connector X2. Connector X2 is not used is this application.
4.3.2.12. Parameter 48: Connector X3 (diagnostic)
This parameter displays the active pins of connector X3. In the standby state, the parameter displays pins 6, 7 and 10 (A=10). Pin 6 is the digital input of the safety socket. If the plug is removed from the safety socket, pin 6 should disappear from the display.When the safety socket is removed, the truck cannot be driven, but the forks can still be lifted.
Pin 7 is the digital input of the lifting limit switch.When the forks are lifted to the top position, the lifting limit switch (S7) opens, and removes the 24-volt supply from digital input pin 7 of connector X3. In this situation, the 7 should disappear from the display. As the pump motor is disabled, the A (pin 10) should also disappear from the display. Pin 10 is the digital output for the pump motor contactor K1.
4.3.2.13. Parameter 49: Connector X4 (diagnostic)
This parameter displays the active pins of connector X4.The possible displayed pins are 3, 4 and 5. Pin 3 is the channel A input signal from the motor encoder bearing and pin 4 is the channel B signal. Pin 5 is active when the electrical brake is released.
You can test the encoder by driving the truck very slowly to observe the signals from the two encoder channels.When you start driving, pin 5 should appear to indicate that the electrical brake has been released. Pin 5 should not be displayed when
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the truck is stationary, as the electrical brake should be engaged. The sequence of pins 3 and 4 depends on the direction of travel. They could, for example, indicate the following sequence: first pin 3, then both pin 3 and pin 4, then only pin 4, then neither, then pin 3 again, and so forth.
4.3.2.14. Parameter 50: Connector X5 (diagnostic)
This parameter displays the active pins of connector X5.The possible displayed pins are 3, 4 and 6. Pin 3 indicates that the tiller arm is in the driving position. Pin 4 indicates that the status LED is illuminated. Pin 6 indicates that the tiller arm is either in the upright or in the bottom position.
When the truck is powered on and no faults have occurred, the status LED should be constantly illuminated, that is, pin 4 should be constantly displayed. If a fault has occurred, both the status LED and pin 4 flash in a pulse sequence that indicates the fault type. In other words, the error code can be counted from the sequence.
Move the tiller arm between the upright and bottom positions to check that the tiller switch works correctly.When the tiller arm is in the upright or bottom position, pin 6 should be displayed and the truck should not respond to driving commands, unless the brake release button is pressed.
4.3.2.15. Parameter 51: Connector X6 (diagnostic)
This parameter displays the active pins of connector X6.The possible displayed pins are 2, 3, 4, 5 and 12 (C=12). Pin 2 indicates that the digital input for the forward driving direction is active. Pin 3 indicates that the digital input for the backward direction is active. Pin 4 indicates that the digital input of the safety switch is active. Pin 5 indicates that the digital input of the brake release button is active. Pin 12 indicates that the optional digital input is active.
When the truck is driven, pin 2 or 3 is displayed to indicate the driving direction. Pin 4 is normally displayed and disappears when the safety switch is pressed. Pin 5 appears when the brake release button is pressed to enable traction even when the tiller arm is in the upright or bottom position. Pin 12 (C) is displayed constantly, as it is an optional pin that has been hardwired to the 24-volt supply.
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4.3.2.16. Parameter 60:Wheel diameter
This parameter is used to set the diameter of the drive wheel. The value is displayed in millimetres.The nominal wheel diameter is 230 mm.
4.3.2.17. Parameter 61: Gear ratio
This parameter is used to set the gear ratio of the truck’s transmission.The factor has been preset and should not be changed.The default value is 36.04 for 1,300 and 1,600 kg capacity trucks, and 30.1 for 2,000 kg capacity trucks.
4.3.2.18. Parameter 67: BDI curve
This parameter is used to select the algorithm used for battery discharge monitoring.The selection depends on the battery type. Use the following values: 9 for 1,300 kg capacity trucks with AGM batteries, 5 for 1,300 kg capacity trucks with GEL batteries, and 3 for 1,600 kg and 2,000 kg capacity trucks.
4.3.2.19. Parameter 68: BDI reset
This parameter sets the voltage value at which the system displays full battery charge.The default value is 25.08 V.
4.3.2.20. Parameter 69: BDI timer
This parameter determines a time period for battery discharge monitoring. Use the preset value. Do not change.The default values are 150.00 s for 1,300 kg capacity trucks, and 240.00 s for 1,600 kg and 2,000 kg capacity trucks.
4.3.2.21. Parameter 81: Lift cut-off
This parameter controls the lift cut-off function.When it is active, that is, set to 1, lifting is disabled when the low battery warning is triggered.The low battery warning level is set with parameter 175.
4.3.2.22. Parameter 98: Stop mode tiller
This parameter controls how the controller decelerates when the tiller arm is removed from the driving position.There are three choices, indicated by the number 1, 2 or 3.The default and
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recommended value is 2. Its advantage is that it reduces the wear of the electrical brake.The alternatives are:
1. The motor’s power feed is cut and the brake is applied at the same time.
2. The motor’s deceleration ramp is applied and the brake is engaged after the truck has come to a standstill.
3. The motor’s deceleration ramp is applied and the brake engaged at the same time.
4.3.2.23. Parameter 107:Warn. temp. contr.
This parameter sets the temperature level for the controller’s high temperature warning.The value is entered in degrees Celsius (°C) and can be between 50 and 79.The default value is 70, which should not be changed.
4.3.2.24. Parameter 133: Acceleration
This parameter controls the rate at which the truck accelerates when the accelerator is moved to request traction. Acceleration is given in km/h/s with an accuracy of two decimals and in the range from 0.50 to 6.00.The default value is 2.80 for 1,300 kg capacity trucks, and 3.60 for 1,600 and 2,000 kg capacity trucks.
4.3.2.25. Parameter 134: Deceleration
This parameter controls the rate at which the truck decelerates when the accelerator is released to request stopping. Deceleration is given in km/h/s with an accuracy of two decimals and in the range from 0.50 to 6.00.The default value is 2.80 for 1,300 kg capacity trucks, and 3.60 for 1,600 and 2,000 kg capacity trucks.
4.3.2.26. Parameter 137: Smoothing curve
This parameter affects the smoothing of the motor control curves. Its range is from 0 to 9, and the default setting is 5 for all truck models.This value should not be changed.
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4.3.2.27. Parameter 138: Progress. curve
This parameter affects the progression of the motor control curves. Its range is from 0 to 100, and the default setting is 75 for all truck models.This value should not be changed.
4.3.2.28. Parameter 139: Reverse braking
This parameter controls the rate at which the truck decelerates when the accelerator is moved to the opposite direction of movement, that is, when performing reverse braking.The deceleration is given in km/h/s with an accuracy of two decimals and in the range from 0.50 to 6.00.The default value is 4.80 for all truck models.
4.3.2.29. Parameter 142: Dec. belly & tiller
This parameter controls the rate at which the truck decelerates when the truck is driven in the direction of the tiller arm and the safety button is pressed.The deceleration is given in km/h/s with an accuracy of two decimals and in the range from 0.50 to 9.00. The default value is 9.00 for all truck models.
4.3.2.30. Parameter 175: Level low batt.
This parameter sets the battery discharge level at which the low battery warning is triggered.The warning is triggered, if the battery level is below the set level for over three seconds.The parameter also sets the level at which the lift cut-off function activates (parameter 81 controls the lift cut-off function).The value range is from 1 to 5.The default value is 2 for 1,300 kg capacity trucks, and 1 for 1,600 and 2,000 kg capacity trucks.
4.3.2.31. Parameter 176: Low batt. speed
This parameter sets the speed reduction when the low battery warning is triggered. It sets the percentage of maximum speed (set by parameters 211 and 216) that is allowed when the low battery warning is triggered.The value range is from 10% to 100%, and the default value is 33 for all truck models.
4.3.2.32. Parameter 211: Max. speed FWD
This parameter sets the maximum speed permitted in the forward direction.The value range is from 0.50 to 6.00 km/h.The default
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value is 5.80 km/h for 1,300 kg capacity trucks, and 6.00 km/h for 1,600 and 2,000 kg capacity trucks.
4.3.2.33. Parameter 216: Max. speed BWD
This parameter sets the maximum speed permitted in the backward direction.The value range is from 0.50 to 6.00 km/h. The default value is 5.80 km/h for 1,300 kg capacity trucks, and 6.00 km/h for 1,600 and 2,000 kg capacity trucks.
4.3.2.34. Parameter 221: Opt. speed limit 1
This parameter sets the optional speed reduction. It sets the percentage of the maximum speed permitted when using the option.The value range is from 10% to 100%, and the default value is 100%.The option is not used in this application.
4.3.2.35. Parameter 222: Brake rel. speed
This parameter sets the speed reduction when using the brake release function. It sets the percentage of maximum speed (set by parameters 211 and 216) that is allowed when the low battery warning is active.The value range is from 10% to 100%, and the default value is 33 for all models.
4.3.2.36. Parameter 223:Tiller type
This parameter sets the type of the installed tiller arm position switch. It has two values:“0” refers to an NO type switch and “1” refers to an NO/NC type switch.The default value is “1”. Do not change.
This parameter displays the current error code, if any. Refer to Section 4.3.3 Fault codes for an explanation of the possible error codes.
4.3.2.38. Parameter 251: Program throttle
This parameter is used to program the voltage range of the accelerator potentiometer into the controller.This procedure must be performed, if either the controller or the accelerator module in the tiller arm head is replaced. It can also be performed, if the truck does not seem to be responding correctly to the accelerator.
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To program the voltage range:
1. Scroll to the Program throttle parameter.The console displays a value of “0”.
2. Press either the left or the right arrow key to activate the cursor.
3. Press the upward arrow key to change the value to “1”.
4. Press the Enter key to initiate the programming procedure.
5. During the 15-second programming period:
a. Move the accelerator smoothly to the maximum forward value.
b. Keep it held for one second.
c. Move it to the maximum backward value.
d. Keep it held for one second.
e. Return it to the neutral value.
6. If the procedure was successfully completed, the parameter value returns to “0” automatically.
The traction motor is disabled while the programming procedure is carried out.
NOTE
4.3.3. Fault codes
When a fault occurs while the truck is operated, truck functions are disabled and the status LED flashes to indicate a fault.The status LED flashes in a particular sequence, depending on the fault.The error code can be determined from the sequence. If the truck is equipped with a display unit, it displays the numerical error code.The error code can also be read with the console by accessing the Error message parameter (249).This section presents the possible error codes with explanations.
4.3.3.1. Error:Watchdog
This fault does not have a numerical error code. It can be determined from the status LED.When the Watchdog error is
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triggered, the status LED flashes with the following sequence: pulse duty cycle 1:1 and frequency 1.25 Hz.
This error signifies an internal fault in the controller.When triggered, it disables the drive and digital outputs.The controller is faulty and must be replaced.
4.3.3.2. Error: RAM fault
This fault does not have a numerical error code. It can be determined from the status LED.When the RAM fault error is triggered, the status LED flashes with the following sequence: pulse duty cycle 1:3 and frequency 2.1 Hz.
This error signifies an internal fault in the controller.When triggered, it disables the drive and digital outputs.The controller is faulty and must be replaced.
4.3.3.3. Error: FLASH fault
This fault does not have a numerical error code. It can be determined from the status LED.When the FLASH fault error is triggered, the status LED flashes with the following sequence: pulse duty cycle 3:1 and frequency 2.1 Hz.
This error signifies an internal fault in the controller.When triggered, it disables the drive and digital outputs.The controller is faulty and must be replaced.
4.3.3.4. Error 2: New software version
This fault has error code number 2.The status LED indicates this fault by repeating the following sequence: two pulses and a pause.
This error appears only when a new software version is being loaded into the controller. It disables the drive and digital outputs. Reload the software as instructed.
4.3.3.5. Error 3: Overcurrent from power stage
This fault has error code number 3.The status LED indicates this fault by repeating the following sequence: three pulses and a pause.
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When this error occurs, the drive is disabled.This error can occur if the controller was loaded for a long period at its current limit. The fault should not appear as long as motor speed monitoring functions correctly.The error can also appear, if a parameter that influences the controller current or the overcurrent shutdown level was modified.
Check the signals from the encoder bearing while the traction motor operates.The signals of channels A and B (pins 3 and 4 of controller connector X4) should appear in the correct sequence. If the sequence is incorrect, check the encoder cable and connections, and change the encoder if necessary.
If the problem is due to altered parameters, it may be resolved by returning to a previous parameter set.
4.3.3.6. Error 4: Low battery voltage
This fault has error code number 4.The status LED indicates this fault by repeating the following sequence: four pulses and a pause.
This error is triggered when the measured battery voltage drops below the level set with parameter 175 for more than three seconds. It causes the traction speed to be reduced to the level set with parameter 176. It also causes the lift cut-off function to activate, if it is enabled with parameter 81. If the battery voltage drops below the value set with parameter 173 (not accessible with the console) for more than three seconds, the controller is shut down.This fault can be reset only by switching the controller supply off and on.
This error can also be triggered, if there are too great voltage drops in the controller supply cables. Check the condition of the battery and the controller supply cabling.
4.3.3.7. Error 5: Battery overvoltage
This fault has error code number 5.The status LED indicates this fault by repeating the following sequence: five pulses and a pause.
This error is triggered when the measured battery voltage exceeds the value set with parameter 174 (not accessible with the console) for more than three seconds. It is also triggered if
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the battery voltage exceeds 150% of the nominal voltage.This fault should not occur, if the battery and the connections to the controller are intact (assuming that parameter 174 is correctly set).This error could also result from a damaged power stage in the controller.
Check that the connections between the battery and the controller are in good condition. Check the value of parameter 174, if possible. If the cause cannot be found, change the controller.
4.3.3.8. Error 6: Motor overtemperature
This fault has error code number 6.The status LED indicates this fault by repeating the following sequence: six pulses and a pause.
This error should not occur, as a motor temperature sensor is not used in this application.
4.3.3.9. Error 7: Controller overtemperature
This fault has error code number 7.The status LED indicates this fault by repeating the following sequence: seven pulses and a pause.
This error is triggered if the controller has overheated during operation.This may result from the controller being overloaded for a long period.This error can also result from a fault in the controller’s temperature measurement function.
Check that the controller is mounted according to the instructions so that it is able to dissipate heat efficiently. Check the controller’s output current. It should not exceed the unit’s nominal current. If the fault persists, the controller needs to be replaced.
4.3.3.10. Error 8: Drive signal monitoring
This fault has error code number 8.The status LED indicates this fault by repeating the following sequence: eight pulses and a pause.
This error indicates a fault with the accelerator.The error can be due to an incorrect operating sequence. After the controller is powered up, the following conditions must be true:
• Drive signals (X6:2 and X6:3) must not be present.
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• Speed reduction must be active.
• The brake release switch (S3) must be open. ara>
• The tiller switch (B2) must not indicate driving position.
• The safety switch (S2) must be closed (i.e. not depressed).
• The safety socket (S8) must be closed.
• The speed reference signal (X6:6) must be near 0 V.
Check that the drive signals are working. Access parameter 51 with the console.Test that turning the accelerator in the forward direction provides the drive signal at pin 2 of connector X6 and that backward direction provides the drive signal at pin 3 of connector X6.
4.3.3.11. Error 9: Encoder bearing monitoring
This fault has error code number 9.The status LED indicates this fault by repeating the following sequence: nine pulses and a pause.
This error could indicate a fault in the encoder bearing or a broken connection between the encoder and the controller.
Check the encoder signals from channels A and B at pins 3 and 4 of connector X4. Refer to Section 4.3.2.13 Parameter 49: Connector X4 (diagnostic).
4.3.3.12. Error 10: Safety switch monitoring
This fault has error code number 10.The status LED indicates this fault by repeating the following sequence: ten pulses and a pause.
This error indicates a fault with the safety switch.The error can be due to an incorrect operating sequence. After the controller is powered up, the following conditions must be true:
• Drive signals (X6:2 and X6:3) must not be present.
• Speed reduction must be active.
• The brake release switch (S3) must be open.
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• The tiller switch (B2) must not indicate driving position.
• The safety switch (S2) must be closed (i.e. not depressed).
• The safety socket (S8) must be closed.
• The speed reference signal (X6:6) must be near 0 V.
Use the console to check that there is a signal at pin 4 of connector X6. Refer to Section 4.3.2.15 Parameter 51: Connector X6 (diagnostic).
This fault has error code number 11.The status LED indicates this fault by repeating the following sequence: eleven pulses and a pause.
This error indicates a fault with the tiller switch.The error can be due to an incorrect operating sequence. After the controller is powered up, the following conditions must be true:
• Drive signals (X6:2 and X6:3) must not be present.
• Speed reduction must be active.
• The brake release switch (S3) must be open.
• The tiller switch (B2) must not indicate driving position.
• The safety switch (S2) must be closed (i.e. not depressed).
• The safety socket (S8) must be closed.
• The speed reference signal (X6:6) must be near 0 V.
Use the console to check that there is a signal at pin 6 of connector X5. Refer to Section 4.3.2.14 Parameter 50: Connector X5 (diagnostic).
4.3.3.14. Error 12: Accelerator monitoring
This fault has error code number 12.The status LED indicates this fault by repeating the following sequence: twelve pulses and a pause.
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This error indicates a fault with the accelerator.The error can be due to an incorrect operating sequence. After the controller is powered up, the following conditions must be true:
• Drive signals (X6:2 and X6:3) must not be present.
• Speed reduction must be active.
• The brake release switch (S3) must be open.
• The tiller switch (B2) must not indicate driving position.
• The safety switch (S2) must be closed (i.e. not depressed).
• The safety socket (S8) must be closed.
• The speed reference signal (X6:6) must be near 0 V.
Use the console to check that the voltage value from the accelerator to pin 6 of connector X6 is close to 0 V when the accelerator is in the neutral position.The value can be checked with parameter 30 (refer to Section 4.3.2.8 Parameter 30:Throttle value (diagnostic)).
4.3.3.15. Error 14: EEPROM fault
This fault has error code number 14.The status LED indicates this fault by repeating the following sequence: fourteen pulses and a pause.
This error signifies an internal fault in the controller.The controller is faulty and must be replaced.
4.3.3.16. Error 15: Unrealistic U/f relationship
This fault has error code number 15.The status LED indicates this fault by repeating the following sequence: fifteen pulses and a pause.
This error indicates that there is a problem with the parameters that control the U/f relationship of the drive.
The error can be resolved by returning to a previous parameter set.
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4.3.3.17. Error 16: Unrealistic speed input transfer function
This fault has error code number 16.The status LED indicates this fault by repeating the following sequence: sixteen pulses and a pause.
This error indicates that there is a problem with the parameters that control the speed input transfer function.
The error can be resolved by returning to a previous parameter set.
This fault has error code number 17.The status LED indicates this fault by repeating the following sequence: seventeen pulses and a pause.
This error indicates that the two tiller switch signals are not complementary.
Use the console to check the operation of the tiller switch (signals X5:3 and X5:6). Refer to Section 4.3.2.14 Parameter 50: Connector X5 (diagnostic).
4.3.3.19. Error 18: Speed reduction monitoring
This fault has error code number 18.The status LED indicates this fault by repeating the following sequence: eighteen pulses and a pause.
This error indicates a fault with the optional speed reduction function.The optional function is not used in this application.The option connection on connector X6 is bridged to the 24-volt supply.
The error can be due to an incorrect operating sequence. After the controller is powered up, the following conditions must be true:
• Drive signals (X6:2 and X6:3) must not be present.
• Speed reduction must be active.
• The brake release switch (S3) must be open.
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• The tiller switch (B2) must not indicate driving position.
• The safety switch (S2) must be closed (i.e. not depressed).
• The safety socket (S8) must be closed.
• The speed reference signal (X6:6) must be near 0 V.
Use the console to check that there is a signal at pin 12 (C) of connector X6. Refer to Section 4.3.2.15 Parameter 51: Connector X6 (diagnostic).
4.3.3.20. Error 19: Brake release monitoring
This fault has error code number 19.The status LED indicates this fault by repeating the following sequence: nineteen pulses and a pause.
This error indicates a fault with the brake release function.The error can be due to an incorrect operating sequence. After the controller is powered up, the following conditions must be true:
• Drive signals (X6:2 and X6:3) must not be present.
• Speed reduction must be active.
• The brake release switch (S3) must be open.
• The tiller switch (B2) must not indicate driving position.
• The safety switch (S2) must be closed (i.e. not depressed).
• The safety socket (S8) must be closed.
• The speed reference signal (X6:6) must be near 0 V.
Use the console to check that pressing the brake release button provides a signal at pin 5 of connector X6. Refer to Section 4.3.2.15 Parameter 51: Connector X6 (diagnostic).
4.3.3.21. Error 20: Safety socket monitoring
This fault has error code number 20.The status LED indicates this fault by repeating the following sequence: twenty pulses and a pause.
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This error indicates a fault with the safety socket.The error can be due to an incorrect operating sequence. After the controller is powered up, the following conditions must be true:
• Drive signals (X6:2 and X6:3) must not be present.
• Speed reduction must be active.
• The brake release switch (S3) must be open.
• The tiller switch (B2) must not indicate driving position.
• The safety switch (S2) must be closed (i.e. not depressed).
• The safety socket (S8) must be closed.
• The speed reference signal (X6:6) must be near 0 V.
Use the console to check that there is a signal at pin 6 of connector X3 when the safety socket is in place. Refer to Section 4.3.2.12 Parameter 48: Connector X3 (diagnostic).
4.4. Electrical maintenance and repairs
This section provides instructions for specific maintenance procedures.These tasks are not part of the regular maintenance schedule.They are performed when needed. Refer to Section 3.1 Safety guidelines and preparation and Section 3.2 Maintenance guidelines for information on safety and preparation for maintenance tasks.
If other (than those examined below) electrical components fail, contact your supplier or local technical support for replacement parts and instructions. If you have a specific electrical maintenance problem that is not answered here or in another part of the manual, contact your supplier or technical support.
4.4.1. Battery maintenance
Before performing battery maintenance, take safety precautions appropriate for handling lead-acid batteries and battery fluid. A truck battery carries a considerable amount of stored electrical energy.When handling a battery, battery assembly or battery cell, insulate all the electrical contacts to minimise the risk of a short circuit. Be careful with conductive tools and equipment when working near batteries. Lead-acid batteries contain a
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96 corrosive acid solution.Wear appropriate protective gear such as protective clothing, gauntlets and eyewear. Refer to Chapter 3 Regular maintenance for information on regular battery maintenance procedures. Contact technical support for current information on servicing truck batteries and acquiring a new battery or battery assembly.
There are three possible power source arrangements (see Section 4.1.2 Power source).The 1,300 kg capacity truck has two independent batteries.They are AGM or GEL type batteries, which are mounted in the main chassis of the truck. Both types are service free, and the entire battery must be replaced when it begins to age. Refer to the instructions provided by the battery manufacturer on using and maintaining AGM and GEL batteries. When replacing the batteries, remember to replace them with batteries of equal weight so that the usage safety of the truck is not affected.
Figure 4.5. Power sources of the 1,300 kg capacity truck
The 1,600 and 2,000 kg capacity truck models have a separate battery compartment, which holds a battery cell assembly.The battery assembly consists of 12 wet lead-acid battery cells and has a nominal voltage of 24 V.The truck models can accommodate power sources with varying capacities.The maximum battery capacity is 270 Ah for 1,600 kg capacity trucks and 345 Ah for 2,000 kg capacity trucks.The battery assembly is connected to the truck’s electrical system via connector XG1.
Refer to Section 4.1 Electrical operation for more information on the electrical connections and operation of these trucks.
Figure 4.6. Power source of a 1,600 kg capacity truck
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98 Figure 4.7. Battery assembly
When you suspect that a battery cell or the entire battery assembly is not functioning optimally, check the state of the cells in the assembly by measuring their specific gravity.This measurement provides more reliable information about the condition of a cell than, for example, measuring its voltage. Always refer to the maintenance instructions issued by the manufacturer or supplier of the battery cell or battery assembly. As a guideline, however, the specific gravity measurement of a fully-charged battery cell should be 1.28 to 1.30 at 30°C. A cell is about half-charged if it measures 1.20 and empty at 1.15 or below.
If a battery cell needs to be replaced, refer to the maintenance instructions issued by the cell manufacturer. Remember to use a cell that is identical to the original one in electrical characteristics, size and weight. In circumstances in which several cells are performing badly, it may be wise to replace the entire battery assembly. It is very important that all the characteristics, especially the weight of the new battery assembly is identical to the original one, so that the truck’s usage safety is not affected.The truck’s identification plate indicates the minimum weight of the battery.
Be careful when replacing the battery assembly, as it is very heavy. Use a sufficiently powerful crane or truck to lift the
assembly from its marked lifting points. Never lift the assembly from any other points.When preparing the assembly for lifting, insulate the battery cell contacts to protect against short circuits.
4.4.2. Fuses
The truck's fuses do not require regular checks.They need to be replaced only if they have blown. Never operate a truck with a blown fuse. Replace the fuse before continuing to use the truck. When fuses need to be changed, always replace them with identical components. Never use a fuse of another rating than that recommended by the manufacturer.
The standard truck has two main fuses and an auxiliary fuse in the controller.To access the fuses, open the truck’s main cover.
Figure 4.8. Example of the two main fuses
On the electrical schematic diagram, the main fuses are marked as 1F1 and 2F1 (zones 13 and 15 on page 1). Fuse 1F1 supplies the positive battery feed to the traction controller. It is rated at 70 A on the 1,300 and 1,600 kg capacity trucks, and 100 A on 2,000 kg capacity trucks. Fuse 2F1 supplies the positive battery feed to the K1 pump motor contactor. It is rated at 70 A on all truck models.
The auxiliary controller fuse is mounted in the controller, but can be accessed from the outside.The auxiliary fuse is marked as
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A1F1 in the electrical schematic diagram (zone 20 on page 1). It is rated at 5 A.
Figure 4.9. Auxiliary controller fuse
If the truck is fitted with optional cold store equipment, an additional heater fuse is present.The heater fuse is marked as F51 in the electrical schematic diagram (zone 14 on page 3). It is rated at 5 A.
4.4.3. Replacing a controller
A controller in the truck may encounter an internal fault, which cannot be fixed from the outside. In this case, it is best to replace the entire controller. Contact your supplier or technical support for information on obtaining up-to-date documentation and parts for the truck.The truck cannot be used with a faulty controller.
Turn the main key switch off and disconnect the battery before attempting any maintenance procedures on the controller.When disconnecting the controller, remember to start by removing the positive supply connection first and the negative connection last. When connecting a new controller, connect the negative supply connection first and finish with the positive connection. Pay attention to the polarity markings on the controller, as polarity inversion will damage it. Contact technical support for the latest information regarding controller replacement.
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NOTE
The parameters of the replacement controller must be reprogrammed for the application.
The accelerator module in the tiller arm head may require replacement during the truck’s operating life.The tiller arm head assembly contains the main control devices needed by the operator to use the truck. Its main component is the accelerator. It also houses the lifting controls, the brake release button, the horn button and the safety button. Refer to Chapter 2 Operating the truck for more information on the truck’s control devices. WARNING! Disconnect the battery connector before beginning.
To replace the accelerator module:
1. Begin by locating the two fixing screws on the underside of the head assembly and the two screws on the topside of the assembly. Open the four screws using a 5 mm Allen key.
Figure 4.10. Main fixing screws at the back of the tiller arm head assembly
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Figure 4.11. Main fixing screws in front of the tiller arm head assembly
2. After removing the screws, lift the top section upwards from the edge containing the safety button. Be careful with the end closer to the arm, as lifting it might stress the internal wiring.
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Figure 4.12. Opening the assembly
3. Disconnect the connector from the accelerator module.
4. Remove the accelerator controls from both sides of the assembly by unscrewing them from the axle.Take care not to lose the spring washers.
5. Loosen the two fixing screws holding the accelerator module with a 4 mm Allen key.The screws do not have to be removed, loosening is sufficient.
6. Remove the safety switch carefully by prying it with a flat-head screwdriver.
7. Install the new accelerator module.
8. Replace the safety switch.
9. Tighten the accelerator module fixing screws.
10.Replace the accelerator controls to the assembly. Note the position of the controls: one of the three wings of both
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controls should point in the direction of the arm, that is, downwards when the arm rests in the upright position.
11.Connect the accelerator module connector.
12.Reposition the top section of the assembly on to the bottom section.
13.Tighten the four fixing screws.
Once the accelerator module has been replaced, it should be tested. Begin by programming the voltage range of the accelerator to the truck’s traction controller. For more information on this procedure, refer to Section 4.3.2.38 Parameter 251: Program throttle. After this procedure, thoroughly test the operation of the tiller arm head controls before returning the truck to normal use.
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5. Hydraulic operation and maintenance
This chapter describes the hydraulic system of the truck.The chapter is divided into two main sections.The first section, Hydraulic operation, presents the hydraulic operation of the truck. The second section, Hydraulic maintenance, provides information on maintenance and repair procedures not covered in Chapter 3 Regular maintenance.
Refer to Section 3.1 Safety guidelines and preparation and Section 3.2 Maintenance guidelines for information on safety and preparation for maintenance tasks. Refer to Chapter 2 Operating the truck for operating instructions.
5.1. Hydraulic operation
This section presents the hydraulic operation of the truck. Please ensure that you have the appropriate version of the hydraulic schematics for the truck model under maintenance. Contact your supplier or technical support for information on obtaining up-to-date documentation for your truck model.
The hydraulic schematic diagram illustrates the operation of the hydraulic system. In the following procedures, different parts of the hydraulic system are numbered.These numbers refer to the figure below.
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Figure 5.1. Hydraulic system (TH50 1104)
The principle of the hydraulic operation of the truck is as follows:
Lifting:
1. The electrical motor (1) operates the hydraulic gear pump (2).
2. The hydraulic fluid is pressurised.
3. The fluid pressure is maintained using a relief valve (3), which opens at a certain pressure. In such cases, hydraulic fluid is returned to the fluid tank.The opening pressure of the relief valve is indicated in the hydraulic schematics.
4. The pressurised hydraulic fluid flows through the no-return valve (5) to the lifting cylinder (6).
5. The lifting cylinder piston lifts the forks.
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Figure 5.2. Hydraulic fluid flow during lifting
Lowering
1. The solenoid valve (8) is opened with the lowering switch.
2. Hydraulic fluid flows through a 300 µ sieve (7) back to the fluid tank.
3. As the hydraulic pressure reduces, the lifting cylinder piston retracts and the forks are lowered.
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Figure 5.3. Hydraulic fluid flow during lowering
Various truck models can have different configurations of the hydraulic system.
5.2. Hydraulic maintenance and repairs
The following sections illustrate various hydraulic maintenance procedures not covered in Chapter 3 Regular maintenance.
5.2.1. Replacing gaskets
NOTE
When the gasket of the hydraulic cylinder needs to be replaced, the wiper and guide strips are also replaced.
To replace gaskets:
1. Pull out the piston rod from the cylinder.
2. Remove the wiper from the cylinder using suitable pliers.
3. Pull the old gasket carefully out of the cylinder.
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NOTE Do not use sharp tools.
4. Squeeze the new gasket using round pointed pliers.The groove in the gasket goes inside the cylinder (towards the bottom of the cylinder). Do not scratch the inside walls of the cylinder.
NOTE
Figure 5.4. Squeezing the gasket
5. Attach the new wiper to the cylinder.The wiper prevents dirt from entering the cylinder when the piston rod moves.
6. Insert the piston rod into the cylinder.
5.2.2. Replacing the hydraulic pump
The hydraulic pump and tank assembly is located in the left part of the main chassis when viewed from the front. Depending on the truck model, the assembly is installed either horizontally (1,300 kg capacity truck model) or vertically (1,600 and 2,000 kg capacity truck models).
To replace the hydraulic pump:
1. Remove the main and top covers of the truck.
2. The hydraulic pump and tank assembly is fixed to a bracket, which is fixed to the main chassis. Locate the bolts that fix the bracket to the chassis and open them.
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NOTE
On 2,000 kg capacity trucks, you have to remove the battery pack to gain access to the fixing screws that hold the hydraulic pump and tank assembly.
3. After opening the bolts, turn the assembly out of the chassis to gain access to it.
4. Open the four screws that hold the entire assembly together using a 4 mm Allen key. Be careful when handling the assembly with the screws removed.
Figure 5.5. Removing the hydraulic tank (1,600 kg capacity truck model)
5. Carefully remove the tank and drain out the old hydraulic fluid.
6. Detach the hydraulic hoses from the hydraulic pump and tank assembly.
7. Disconnect the electrical connections from the hydraulic pump motor.
8. Replace the hydraulic pump motor.
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9. Connect the electrical connections to the new hydraulic pump motor.
10.Connect the hydraulic hoses to the hydraulic pump.
11.Attach the hydraulic tank to the hydraulic pump and fasten the four fixing screws.
12.Reattach the entire assembly to the main chassis.
13.On 2,000 kg capacity trucks, reattach the battery pack.
14.Open the filling cap and fill the tank with new hydraulic fluid to half (1,300 kg capacity truck model) or three-quarters (1,600 and 2,000 kg capacity truck models) of its capacity when measured from the bottom of the tank to the filling tube.
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6. Mechanical maintenance
This chapter presents the mechanical maintenance procedures not covered in Chapter 3 Regular maintenance. Refer to Section 3.1 Safety guidelines and preparation and Section 3.2 Maintenance guidelines for information on safety and preparation for maintenance tasks. Refer to Chapter 2 Operating the truck for operating instructions.
6.1. Replacing wheels
A truck has three wheel types: drive, load and castor wheels. Check all the wheels on a truck for damage and wear.The wheels should wear evenly and there should be no flats or holes in the wear surface.The wheels should also turn smoothly on their axles and there should not be play in the bearings. Even wear can be checked by driving the truck on a smooth surface to test that all the wheels turn and the truck rides smoothly. If a wheel or a bearing has sustained damage that affects use or if its surface has worn completely, it should be replaced.
To replace a truck wheel, follow the instructions given below. Never work under the truck if it is supported only by a jack.
WARNING!
6.1.1. Replacing the drive wheel
The drive wheel is located immediately under the tiller arm anchoring point and supports a considerable portion of the truck’s weight.The drive wheel is used to propel and steer the truck. It is attached to the drive motor via the transmission.The tiller arm is used to turn the drive wheel when steering the truck.
To replace the drive wheel:
1. Open the main and the top covers of the truck by loosening the fixing screws enough for the cover to be removed, but do not remove the screws entirely.The screws move a fixing bracket, which holds the cover in place.
2. If you are working on a 2,000 kg capacity truck, skip to step 4. On 1,300 and 1,600 kg capacity trucks: Open the four fixing screws of the bottom steel plate cover. Use a 5 mm
Allen key.
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Figure 6.1. Removing the bottom plate fixing screws
3. Lift the bottom steel plate cover up over the tiller arm. Make sure that none of the control panel wires are damaged.
4. Turn the drive wheel using the tiller arm so that the fixing screws of the wheel can be reached.
5. On 2,000 kg capacity trucks, remove the five wheel fixing screws with a 19 mm wrench. On 1,300 and 1,600 kg capacity trucks, remove the ten wheel fixing screws with a 5 mm Allen key. Do not remove the two countersunk screws, as they hold the planet gear rim in place.
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Figure 6.2. Removing the drive wheel fixing screws on 1,300 and 1,600 kg capacity trucks
6. Lift the truck from under the chassis using a suitable jack so that the drive wheel is lifted off the supporting surface.
7. Remove the old drive wheel.
8. Attach the new drive wheel.
9. Replace all truck covers and test the operation of the drive unit.
6.1.2. Replacing the load wheels
The load wheels are located near the ends of the forks.Their main purpose is to support the weight of the load. Depending on the truck model, there is either a single or a double load wheel in each fork.
To replace single load wheels:
1. Loosen the locking pin from the axle using a 5 mm pin punch.
The locking pin is located on the outside end of the axle.
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2. Raise the forks and lift the truck slightly with a jack.
3. Remove the locking pin from the axle.
4. Remove the load wheel axle.
5. Replace the load wheel and reattach the axle and the locking pin.
To replace double load wheels:
1. Lift the truck using a jack. Place supporting brackets under the truck.
2. Remove the axle bolt using a 8 mm Allen key on both ends of the bolt.
3. Replace the load wheel and reattach the axle bolt.
6.1.3. Replacing the castor wheels
The side-supporting castor wheels are located under the main chassis on either side of the drive wheel.They support the truck when it is driven and prevent it from tilting, as there is only one drive wheel.The castor wheels turn automatically to follow the direction of travel.They are equipped with suspension springs.
To replace the castor wheels:
1. Lift the truck using a jack. Place supporting brackets under the truck.
2. Remove the axle bolt using a 17/19 mm wrench on both ends of the bolt.
3. Replace the castor wheel and reattach the axle bolt.
6.2. Replacing the tiller arm gas spring
This section gives instructions on how to replace the gas spring of the tiller arm.The purpose of the gas spring is to return the tiller arm automatically to the upright resting position. It is a safety device, which must always be fully operational.
To replace the gas spring:
1. Remove the cover from the base of the tiller arm.
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2. Remove the ball joints from both ends of the gas spring using a 13 mm wrench.
3. Replace the gas spring.
4. Attach the ball joints to the tiller arm.
5. Reattach the cover to the base of the tiller arm.
6. Test the operation of the tiller arm.
Figure 6.3. Replacing the tiller arm gas spring
6.3. Lever system maintenance
The lever system is present only on trucks with initial lifting functionality.The system is composed of levers and the initial lifting cylinder between the main chassis and the mast assembly, and push rods under the forks.They operate to lift the mast and fork assembly evenly when initial lifting is used.The following procedures provide instructions for disassembling the system for maintenance purposes.
The bushings in the initial lifting levers must be changed when play has developed in the system.
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WARNING!
These procedures require the truck to be lifted and supported.Take care to support the weight of the truck and the separated components.Take care especially when removing the levers between the main chassis and the mast assembly.
To remove the pushrods:
1. Lift the truck.
2. Remove the locking pins from both ends of the push rods using a 5 mm punch.
3. Remove the shafts from both ends of the push rods. The shafts at the cylinder ends of the push rods cannot be removed by hitting them with a punch.You have to
NOTE
use an inertia hammer to pull the shaft out from the push rod.
4. Remove the push rods.
To remove the wheel forks:
1. Remove the load wheels from the wheel forks.
2. Remove the locking pins and detach the wheel forks.
To remove the hydraulic cylinder lever:
1. Remove the push rods.
2. Remove the circlips from the cylinder axle ends.
3. Remove the axle from the cylinder.There are two washers on each side of the cylinder attachment point.
4. Remove the lever.
To remove the upper and lower levers:
1. Remove the locking pins with a 4 mm punch.
2. Remove the axles. Depending on the lever end, gently hammer the axles out or remove them with an extractor.
3. Remove the bushings from the axle and install new ones.
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