Troubleshooting - Harrington Hoists RHN02D-20A-20D Series Owner's Manual

7.0

Troubleshooting

HAZARDOUS VOLTAGES ARE PRESENT IN THE HOIST AND IN CONNECTIONS BETWEEN
COMPONENTS.
Before performing ANY troubleshooting on the equipment, de-energize the supply of electricity to the equipment,
and lock and tag the supply device in the de-energized position. Refer to ANSI Z244.1, "Personnel Protection -
Lockout/Tagout of Energy Sources."
Only Trained and competent personnel should inspect and repair this equipment.
Symptom
Hoist and/or Trolley
moving in wrong
direction
Hoist and/or Trolley will
not operate

Table 7-1
Cause
Power supply reversed
phased
Improper electrical
connections
Loss of power
Wrong voltage or
frequency
Hoist overload
Motor overheated and
thermal overload
protector has tripped
Improper, loose, or
broken wire in hoist
electrical system
Brake does not
release
Defect in control
transformer
Faulty magnetic
contactor
Faulty Up or Down
Limit Switch
Motor burned out
Troubleshooting Guide
Switch two (2) of the three (3) power supply cord wires at the
power source.
Refer to wiring diagram and check all connections.
Check circuit breakers, switches, fuses and connections on power
lines/cable.
Check voltage and frequency of power supply against the rating
on the nameplate of the motor.
Reduce load to within rated capacity of hoist.
See Trouble Shooting Problem "Motor or brake overheating".
Shut off power supply, check wiring connections on hoist control
panel and inside push-button pendant.
Check motor brake adjustment for proper clearance.
Check transformer coil for signs of overheating. Disconnect
transformer and check for open winding.
Check coil for open or short circuit. Check all connections in the
control circuit. Check for open contactors. Replace as needed.
Replace the Up and/or Down Limit Switch
Replace motor frame/stator, shaft/rotor, and any other damaged
parts.
65
Remedy