5. Follow steps 11 through 14 in previous section, CHAIN
REPLACEMENT WITH CHAIN IN LIFTING MOTOR, to
complete the chain replacement procedure.
NOTE: Inspect chain guides and load sheave for wear,
replace as needed.
LIMIT SWITCH ADJUSTMENT
Refer to Figure 5.
IMPORTANT: Before placing lifting motor in operation, check
the limit switch adjustment. Limit switches are provided to
protect the lifting motor against damage resulting from
overtravel or to allow setting the hook travel within the
factory-set limits of travel. The standard UJC limit switch allows
for the maximum amount of lift, which is 134 ft on 1/2 ton
lifting motor models, 143 ft on the 1 ton models, and 71 ft
on the 2 ton models.
The limit switch adjusting nuts are color-coded gold for the
“UP” limit and silver for the “DOWN” limit. Movement of the limit
switch nuts toward or away from each other increases or
decreases the hook travel respectively.
Adjusting Upper Limit (Gold Nut)
1. Suspend the lifting motor. For single-chained models
operate “UP” until there is a minimum clearance of 2" from
the lifting motor housing and the top of the block. Double-
chained models require a minimum clearance of 1" from the
chain support to the top of the load block.
2. DISCONNECT LIFTING MOTOR FROM POWER SUPPLY
and remove the electrical cover.
3. With a screwdriver, pry the spring guide plate out of the slots
in the limit switch nuts.
4. Turn the slotted gold nut toward its limit switch until the
switch “clicks” then turn two slots farther. Release the spring
guide plate and be sure it slips back into the slots in both
limit switch nuts. Do not disturb the silver slotted nut if it has
been set previously.
Adjusting Lower Limit (Silver Nut)
1. Suspend the lifting motor. Operate “DOWN” to a point where
the slack-end loop of the chain hangs down 6" or more from
the lifting motor housing (or the limit desired in any particular
application allowing the minimum 6"). There should be a
minimum clearance of 1½" between the chain stop and the
bottom of the lifting motor.
2. DISCONNECT LIFTING MOTOR FROM POWER SUPPLY
and remove the electrical cover.
3. With a screwdriver, pry the spring guide plate out of the slots
in the limit switch nuts.
4. Turn the slotted silver nut toward its limit switch until the
switch “clicks,” then turn two slots farther. Release the spring
guide plate and be sure it slips back in the slots in both limit
switch nuts. Do not disturb the gold slotted nut if it has been
set previously.
Check Both Upper and Lower Limits
1. Connect the lifting motor to the power supply. Be sure the
green ground wire is properly grounded.
2. Check the direction of hook travel (See INSTALLING THE
LIFTING MOTOR, page 5).
3. Carefully operate to upper limit and observe if it stops
automatically at desired level. Do not allow load block to run
into the lifting motor housing — this will damage the lifting
motor. Maintain a minimum clearance of 2" from the lifting
motor housing and the load block on single-chained models
and 1" from the chain support to the load block on double-
chained models.
4. Carefully operate to lower limit and observe if it stops
automatically at the desired level. Do not allow slack-end
loop of chain to become taut against lifting motor housing.
This will damage the lifting motor. There should be a
minimum clearance of 1½" between the chain stop and the
lifting motor.
5. If upper and lower limits operate satisfactorily, lifting motor is
ready for use. If they are not as desired, repeat adjustment.
BRAKE
Properly adjusted, this brake will release promptly when
energized. It is capable of both smoothly stopping and securely
holding the rated capacity of the lifting motor. If the lifting motor
develops either undesirable over-travel after a pushbutton is
released (this condition is most noticeable in the lowering
direction) or hesitates to lift the load promptly, the brake should
be adjusted.
Brake Adjustment
Refer to Figure 4.
1. DISCONNECT LIFTING MOTOR FROM POWER SUPPLY
and remove the electrical cover.
2. With reference to Figure 4, the gap between the brake
armature “A” and the field “B” should be checked. The
correct gap is 0.015". Adjustment should not be necessary
until gap reaches 0.040".
8
If the wires running to the limit switches are ever
disconnected for any purpose, be sure to replace
wires in accordance with the correct wiring diagram
(See Figures 7A - 7C).
Failure to follow proper lockout/tagout procedures may
present the danger of electrical shock.
TO AVOID INJURY:
Disconnect power and lockout/tagout disconnecting
means before removing cover or servicing this
equipment.
Country Club Road
P.O. Box 779
Wadesboro, NC 28170 USA
TEL: (800) 477-5003
FAX: (800) 374-6853
Failure to follow proper lockout/tagout procedures may
present the danger of electrical shock.
TO AVOID INJURY:
Disconnect power and lockout/tagout disconnecting
means before removing cover or servicing this
equipment.
Failure to follow proper lockout/tagout procedures may
present the danger of electrical shock.
TO AVOID INJURY:
Disconnect power and lockout/tagout disconnecting
means before removing cover or servicing this
equipment.
For more information contact: Sievert Crane and Hoist, (708) 771-1600, [email protected], www.sievertcrane.com
