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00001996 (REV AC) 627NH October 2014
TROUBLE SHOOTING ALL HOISTS TABLE 7
TROUBLE PROBABLE CASE REMEDY
1. Hook does not respond to the
control station or control device
A.) No voltage at hoist-main line or
branch circuit switch open; branch
line fuse blown or circuit breaker
tripped.
A.) Close switch, replace fuse or reset
breaker.
B.) Phase failure (single phasing,
three phase unit only)-open circuit,
grounded or faulty connection in
one line of supply system, hoist
wiring, reversing contactor, motor
leads or windings.
B.) Check for electrical continuity and repair
or replace defective part.
C.) Upper or lower limit switch has
opened the control circuit.
C.) Press the “other” control and the hook
should respond. Adjust limit switches as
described on page 23.
D.) Open control circuit-open or
shorted winding in transformer,
reversing contactor coil or loose
connection or broken wire in
circuit;mechanical binding in
contactor control station contacts
not closing or opening.
D.) Check electrical continuity and repair or
replace defective part.
E.) Wrong voltage or frequency. E.) Use the voltage and frequency indicated
on hoist identifi cation plate. For three
phase dual voltage unit, make sure the
connections at the voltage change board
are the proper voltage as described on
page 14.
F.) Low Voltage. F.) Correct low voltage condition as described
on page 14.
G.) Brake not releasing-open or shorted
coil winding; armature binding.
G.) Check electrical continuity and
connections. Check that correct coil has
been installed. The coil for three phase
dual voltage unit operates at 230 volts
when the hoist is connected for either 230
volt or 460 volt operation. Check brake
adjustment as described on page 22.
H.) Excessive load. H.) Reduce loading to the capacity limit of
hoist as indicated on the identifi cation
plate.
2.) Hook moves in wrong
direction.
A.) Wiring connections reversed at
either the control station or terminal
board (single phase unit only).
A.) Check connections with the wiring
diagram.
B.) Failure of the motor reversing switch
to effect dynamic braking at time of
reversal (single phase unit only).
B.) Check connections to switch. Replace a
damaged or faulty capacitor
C.) Phase reversal (three phase unit
only).
C.) Refer to installation instructions on page
14
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