Special Precautions; Discharging The Capacitors - Yale 524150797 Maintenance Manual

0620 YRM 1513

DISCHARGING THE CAPACITORS

WARNING
The capacitor in the transistor controller can hold
an electrical charge after the battery is disconnec-
ted. To prevent electrical shock and personal in-
jury, discharge the capacitor before inspecting or
repairing any component. Wear safety glasses.
Make certain the battery has been disconnected.
DO NOT use a screwdriver to discharge the trac-
tion motor controller.
WARNING
To avoid personal injury and prevent electrical
shock, perform the following steps before per-
forming any troubleshooting or adjustments, and
connecting or disconnecting a handset or PC.
CAUTION
To avoid controller damage, always disconnect
the battery. Discharge the capacitor and never put
power to the controller with any power wire dis-
connected. Never short any controller terminal or
motor terminal to battery. Make sure to use proper
procedures when servicing the controller.
1. Turn the key switch to the OFF position and dis-
connect the battery.
2. Remove the drive unit compartment cover to ac-
cess the controller. See GeneralGeneralGeneral.
3. Discharge the capacitors in the controllers by con-
necting a 200-ohm, 2-watt resistor across the
controller's B+ and B− terminals using insulated
jumper wires. See Figure 3. DO NOT short across
the motor controller terminals with a screwdriver
or jumper wire. Remove the 200-ohm, 2-watt re-
sistor before reconnecting the battery.

Special Precautions

1. CONTROLLER
2. POSITIVE CONNECTION
3. INSULATED JUMPER WIRES
4. 200-OHM, 2-WATT RESISTOR
5. NEGATIVE CONNECTION
Figure 3. Discharging the Capacitors
Special Precautions
3