Coffing Hoists Concert Series Operating, Maintenance & Parts Manual page 8

Country Club Road
P.O. Box 779
Wadesboro, NC 28170 USA
TEL: (800) 477-5003
FAX: (800) 374-6853
5. Remove the two chain guide plate screws (Ref. No. 2) and
the nearest chain guide plate. Be careful not to lose the two
spacers that are between the chain guide plates.
NOTE: Inspect chain guides and load sheave for wear, replace
as needed.
6. Lay the new chain over the load sheave. Allow about 15" of
chain below the lifting motor on the slack end. Be sure the
welds of the upstanding links are out away from the load
sheave and that proper orientation is observed for attachment
of the dead end. Also be sure the load hook assembly (if
already attached to the chain) is toward the center of the lifting
motor or to your right as you face the load sheave.
7. Replace the chain guide plate and the chain guide. Grease
the splined shafts that project from both the housing and
the motor.
8. Place the motor coupling on the splined shaft and carefully
fit the two lifting motor sections together. Be sure the dead-
end nut, the top hook and the chain support (double-chained
lifting motors only) are all in place. On single-chained lifting
motors, the hook shank goes in the center hole; on double-
chained lifting motors, it goes in the off-center hole. Be
careful not to pinch any of the wiring. Turn the lifting motor
on its side and replace the four screws and tighten securely.
9. Follow steps 11 through 14 in the previous section, CHAIN
REPLACEMENT WITH CHAIN IN LIFTING MOTOR, to
complete the chain replacement procedure.
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 UJL 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
For more information contact: Sievert Crane and Hoist, (708) 771-1600, parts@sievertelectric.com, www.sievertcrane.com
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.
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).
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.
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.
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