9.
Moving one traveling nut toward the other
increases hook travel and away from the other
decreases the travel. Now, turn the nut nearest
the switch indicated as the "LOWER LIMIT
SWITCH" until it just breaks the limit switch
contacts. An audible click will be heard as the
switch opens. Continue to rotate the nut toward
the switch an additional two full teeth on single
limit switch gear reduction or one full tooth on
double limit switch gear reduction, refer to Table
I.
10.
Reposition the guide plate in the next slot and
securely tighten screws.
11.
Reconnect hoist to power supply, and check the
stopping point of hook by first raising the hook
about 10 inches, then lower the hook by jogging
cautiously until the lower limit switch stops the
downward motion. The stopping point of hook
should be the desired lower position. If not,
repeat the above instructions.
12.
Double check setting by raising the hook about
2 feet and then run the hook into the lower limit
with the v (DOWN) control held depressed.
13.
Fine adjustment of the lower limit setting may
be obtained by inverting the guide plate in Step
10. The offset on the plate gives adjustments
equivalent to 1/2 notch, see Table I for the
"Hook Travel Per Notch of Limit Switch Nut".
When inverting the plate, it may be necessary to
use the notch adjacent to the one used in the
preliminary setting.
TABLE I
ENCLOSED TYPE LIMIT SWITCHES
Hook Travel Per Notch of Limit Switch Nut
SECTION D - TROUBLE SHOOTING
All Hoists
TROUBLE
PROBABLE CAUSE
CHECK AND REMEDY
1.
Hook does not
a)
No voltage at hoist - main line
a) Close switch, replace fuse or reset breaker.
respond to the
or branch circuit switch open;
control station.
branch line fuse blown or cir-
cuit breaker tripped.
b)
Phase failure (single phasing,
b) Check for electrical continuity and repair
three phase unit only) - open
or replace defective part.
circuit, grounded or faulty con-
nection in one line of supply
system, hoist wiring, reversing
contactor, motor leads or wind-
ings.
c)
Upper or lower limit switch has
c) Press the "other" control and the hook
opened the motor circuit.
should respond. Adjust limit switches as
described on page 16.
d)
Open control circuit--open or
d) Check electrical continuity and repair or
shorted winding in transformer,
replace defective part.
reversing contactor coil or
speed selecting relay coil; loose
connection or broken wire in
circuit; mechanical binding in
contactor or relay; control station
contacts not closing or opening.
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