OZ Lifting Products ELECTRIC Serie Manuel De L'opérateur page 19

TROUBLESHOOTING:
Symptom Cause
Hoist will not Loss of power
operate
Wrong voltage or frequency
Hoist overload
Improper, loose or broken wire
in the hoist electrical system
Brush wear
Fuses burned out
Motor burned out
Hoist lifts but Faulty switch in pendant
will not lower
Broken conductor in pendant
cord
Hoist lowers Hoist overload
but will not lift
Worn friction clutch
Broken conductor in pendant
cord
Faulty switch in pendant
Low voltage in hoist's power
supply
Hoist will Hoist overload
not lift rated
Low voltage in hoist's power
load or does
supply
not have the
Faulty friction clutch
proper lifting
speed
Load drifts Motor demagnetized
excessively
when hoist is
stopped
Improper gear oil
Hoist operates Loose connection in circuit
intermittently
Collectors making poor contact
Broken conductor in pendant
cord
Table 8-7 Troubleshooting Guide
Remedy
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.
Shut off power supply, check wiring connections on hoist control panel
and inside push button pendant.
Inspect both motor brushes per Table 8-2 and replace if necessary.
Replace fuses.
Replace motor frame/stator, shaft/rotor and any other damaged parts.
Check electrical continuity. Check electrical connections. Replace or
repair as needed.
Check the continuity for each conductor in the cable. If one is broken,
replace the entire cable.
Reduce load to within rated capacity of hoist.
Repair by a qualified person trained in the repair of hoists and proper
friction clutch adjustment procedures. Replace as needed.
Check the continuity for each conductor in the cable. If one is broken,
replace the entire cable.
Check electrical continuity. Check electrical connections. Replace or
repair as needed
Determine cause of low voltage and bring to within plus or minus 5% of
the voltage specified on the motor nameplate. The voltage should be
measured at the hoist contactor.
Reduce load to within rated capacity.
Determine cause of low voltage and bring to within plus or minus 5% of
the voltage specified on the motor nameplate. The voltage should be
If abnormal operation or slippage occurs do NOT attempt to disassem-
ble or adjust the Mechanical Load Brake with Friction Clutch. Replace
the worn or malfunctioning Mechanical Load Brake with Friction Clutch
as an assembly with a new, factory adjusted part.
Motor demagnetizing is generally caused from using the hoist beyond
its duty rating. Replace stator assembly and reduce usage to comply
with the duty rating stated.
Replace oil with the correct gear oil.
Check all wires and terminals for bad connections. Replace as needed.
Check movement of spring loaded arm, weak spring, connections and
shoe. Replace as needed.
Check for intermittent continuity in each conductor in the pendant cord.
Replace the entire pendant cord if continuity is not constant.
EN pg.19