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6.
Hook lowers but will
not raise
A) Lifting motor overload
A) Reduce load to within rated
capacity of chain hoist.
B) Low voltage
B) Determine cause of low voltage
and bring up to within plus or
minus 10% of the voltage
specified
on
the
motor.
Measure voltage at the lifting
motor in terminal block power
input.
C) “UP” circuit open
C) Check circuit for loose
connections
D) Broken conductor in
pushbutton cable
D) Check each conductor in the
cable. If one is broken, replace
entire cable.
E) Worn overload limiting
clutch
E) Adjust or replace overload
clutch assembly.
F) Loose screw clamps
F) Ensure that screw clamps are
tightened on the terminal
blocks.
7.
Motor overheats
A) Excessive load
A) Reduce load to within rated
capacity of chain hoist
B) Low voltage
B) Determine cause of low
voltage and bring up to within
plus or minus 10% of the
voltage specified on the motor.
Measure voltage at the lifting
motor in terminal block power
input.
C) Frequent starting or
reversing
C) Excessive inching, jogging or
reversing should be avoided
since this type of operation will
drastically shorten the life of
motor and brake.
D) Brake dragging
D) Replace brake assembly
8.
Lack of proper lifting
speed
A) Chain hoist overload
A) Reduce load to within rated
capacity of chain hoist
B) Brake dragging
B) Replace brake assembly
C) Low voltage
C) Determine cause of low
voltage and bring up to within
plus or minus 10% of the voltage
specified on the motor. Measure
voltage at the lifting motor in
terminal block power input.
D) Overload limiting clutch
intermittently slipping
D) Adjust or replace overload
limiting clutch assembly.
Summary of Contents for DU903
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