Testing The Interlock Relay; Operation; Testing; Replacing The Charger - Taylor-Dunn SS-025-34 Operation, Maintenance, And Replacement Parts Manual

Battery Charger
TESTING THE INTERLOCK
RELAY

Operation

The Interlock Relay disables the vehicle from running whenever
the charger is connected to a working AC power source. When
the charger is plugged in, the relay contacts open and break
the Key Switch connection to the speed controller. The Interlock
Relay is available for built-in chargers only. Not all built-in
chargers are equipped with this relay. To identify chargers that
are equipped with the Interlock Relay:
• Inspect the charger wire harness where it enters the charger
cabinet for two Violet/Black wires. If these wires are present
then the charger is equipped with the Interlock Relay.

Testing

1. Make sure the start switch is in the "OFF"
position, then remove the key.
2. Place the forward-reverse switch in the center
"OFF" position.
3. Set the park brake.
4. Place blocks under the front wheels to prevent
vehicle movement.
5. Disconnect the charger from the AC power source.
6. Disconnect the two Violet/Black wires at the charger.
7. Set the DMM to check for continuity and connect the DMM
leads to the Violet/Black wires going into the charger.
• The DMM should indicate a closed circuit. If the DMM
indicates an open circuit, then the relay or the wires to the
relay have failed. Stop here and repair the problem.
8. Connect the charger to a working AC power source.
• The charger should turn on. If the charger does not turn on
then their may be a problem with the AC power source or
the AC wiring to the charger. Refer to the beginning of this
section for charger troubleshooting. DO NOT continue until
you have confirmed that the AC power source is working.
• The DMM should indicate an open circuit. If it still indicates
a closed circuit, then the relay or the wires to the relay have
failed. Stop here and repair the problem.
• If the DMM indicates an open circuit then the interlock relay
is functioning normally.
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REPLACING THE CHARGER

Only used OEM components from Taylor-Dunn.
Chargers not tested by Taylor-Dunn (or intended
for use on other Taylor-Dunn vehicles) may have
unanticipated interaction and/or interference with
the vehicles control system resulting in unsafe
operation or damage to the electrical system.
The charger should only be replaced with the same type
originally equipped with the vehicle or a charger approved by
Taylor-Dunn for use with this vehicle.
The motor control system is equipped with a charger interlock
circuit. It disables the control system when the charger is
plugged in. The interlock is built in to the charger and/or is
incorporated in the portable charger receptacle.
The interlock serves two purposes:
1) Disables the motor control system preventing the vehicle
from operating while the charger cord is connected.
2) Turns off the motor control system protecting it from
electrical interference generated by the charger.
Note: The Signet charger comes equipped with a long fully
insulated AC cord that can be cut to length as needed
for the vehicle application. Do not cut the AC cord
and splice to the existing AC cord in the vehicle.
Cutting and splicing the Signet AC cord will void the
charger warranty
SLA batteries must be charged with a charger
configured for SLA batteries. Use of any other
charger will result in damage to the batteries and
premature failure of the batteries.