COMEUP Chain Hoist (Ver:02) - Manual (Page 15)

13
Before performing any troubleshooting on the chain hoist, de-energize the supply of electricity
as hazardous voltages are present in the hoist and in connections between components.
Trouble Shootings
Symptom Possible cause Remedy
Hoist will not
operate
Loss of power or wrong voltage/frequency
Check power supply against the rating on the
name plate
Power cutoff switch lights red
Reduce load to within rated capacity of hoist
and reset by manual
Motor overheated
Take a rest and perform the hoist according to
its duty cycle percentage rated at 25%ED
Motor burned out Replace motor
Brake does not release Check or replace brake assembly
Improper installation or wearing of carbon
brush
Check or replace carbon brush
Escape or open circuit of carbon brush lead Check or replace carbon brush lead
Can lift, but fail to
lower
Down circuit open Check down limit switch for malfunction
Malfunction of the Down contact of the pendant
switch
Replace pendant switch
Can lower, but fail
to lift
Down circuit open Check down limit switch for malfunction
Hoist overloaded Reduce load to within rated capacity of hoist
Considerable voltage drop
Applied voltage shall fall into ±10% of rated
voltage on the name plate.
Fault friction clutch
If abnormal operation or slippage occurs do not
attempt to disassemble or adjust the friction
clutch. Replace the malfunctioning friction
clutch with a new or factory adjusted part.
Malfunction of the Up contact of the pendant
switch
Replace pendant switch
Short circuit
Melted B contact of pendant switch Replace pendant switch
Burnt diode Replace diode and pay attention to its poles
Burnt D type resistor Replace resistor
Having too much carbon powder on carbon
brush holder
Disassembly the motor and clean carbon
powder
Burnt motor Replace motor
Fail to lift the load
rated
Hoist overloaded Reduce load
Considerable voltage drop
Applied voltage shall fall into ±10% of rated
voltage on the name plate
Incorrect carbon brush specification or too
short
Replace carbon brush
Burnt, deformation of carbon brush holder Replace carbon brush holder
Load drifts
excessively when
hoist is stopped
The gap of ratchet brake is too large Adjust the ratchet brake
Malfunction of pressed spring of ratchet brake Replace the pressed spring
Oil leakage
Improper installation of cap screw Proper installation of cap screw
Damaged or deformed oil packing Replace oil packing
Fail to install oil packing Install oil packing