DISCHARGING THE INTERNAL
CAPACITORS
When working with the electrical systems of the
truck, it is necessary to discharge the internal
capacitors of the controllers associated with each
circuit affected.
WARNING
Capacitors inside the controllers can hold an
electrical charge after the battery is disconnected.
Discharge the internal capacitors before servicing
the electrical system to prevent injury or
electronic damage.
1.
Move the lift truck to a safe, level area and
completely lower the mast. Turn the key switch
to the OFF position and attach a DO NOT
OPERATE tag to the control handle. Block the
drive wheel to prevent unexpected 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 controller B+ and B-
terminals of the motor controller for 10 seconds.
Remove the resistor after discharging the
capacitors. See Figure 2.
1. POSITIVE CONNECTION (B+)
2. NEGATIVE CONNECTIONS (B-)
3. INSULATED JUMPER WIRES
4. 200-OHM, 2-WATT RESISTOR
Figure 2. Discharging the Internal Capacitors
STATIC STRAP
The static strap is a rubber strap molded with non-
sparking metal inside. It is mounted to the frame of
the lift truck near the lower mast mounting plate.
See Figure 3. Static electricity builds during
operation of the lift truck. The tires of the lift truck
isolate the metal components of the truck from the
floor. The strap allows limited conductivity between
the lift truck frame and the floor to disperse the
static charge. If the static strap is removed or
damaged, the static charge may build. This can
cause damage to electronic components of the lift
truck and may discharge with a spark when the
forks or other parts of the lift truck frame contact
items that permit grounding to the floor. Sparks
caused by static electricity can cause an explosion
when it occurs near flammable materials or around
batteries which vent flammable gasses during
normal operation. Check that the static strap is
present and is in good working condition before
operating the lift truck. Replace the strap if
necessary.
General
2200 SRM 1612
2