Special Precautions
DISCHARGING THE INTERNAL
CAPACITORS
When working with the electrical systems of the truck, it is
necessary to discharge the internal capacitors of the con-
trollers associated with each circuit affected.
WARNING
Capacitors inside the controllers can hold an elec-
trical charge after the battery is disconnected.
Discharge the internal capacitors before servicing
the electrical system to prevent injury or elec-
tronic damage.
1.
Move the lift truck to a safe, level area and completely
lower the mast. Turn the key switch to the
OFF
posi-
tion and attach a
DO NOT OPERATE
tag to the con-
trol handle. Block the drive wheel to prevent unexpec-
ted movement.
2.
Disconnect the battery power cable connector from the
truck connector located on the right side of the frame.
Pull the battery cable connector handle to separate the
battery connector from the truck connector.
3.
Remove the operator compartment cover.
4.
Discharge the internal capacitor in the controllers by
connecting a 200-ohm, 2-watt resistor across the con-
troller B+ and B− terminals of the motor controller for
10 seconds. Remove the resistor after discharging the
capacitors. See Figure 4.
ELECTROMAGNETIC SHIELD
WARNING
Never operate Power Assist Steering models with
the Electromagnetic Shield removed.
A metallic shield is installed between the MDU and brake
assembly and the steering assembly on power assist steer-
ing units. This shield deflects the electromagnetic field gen-
erated by the MDU and brake assembly which can interfere
with the operation of the torque sensor. Make certain that
the Electromagnetic Shield is reinstalled before operating
the lift truck after servicing to prevent erratic operation of
the power assist steering function.
1. CONTROLLER
2. POSITIVE CONNECTION (B+)
3. INSULATED JUMPER WIRES
4. 200-OHM, 2-WATT RESISTOR
5. NEGATIVE CONNECTIONS (B−)
Figure 4. Discharging the Controller
2200 SRM 1640
Special Precautions
3
