Trouble Shooting - Coffing Hoists Concert Series Operating, Maintenance & Parts Manual

TROUBLE SHOOTING

Always disconnect unit from the power supply system before
removing lifting motor covers or the back cover of control
station.
––– Probable Cause –––
Hook fails to stop at end of travel
1. Limit switch not operating
2. Brass limit switch nuts not moving on shaft
3. Reversing contactor malfunctioning
Lifting motor does not respond to pushbutton
1. Power failure in supply lines
2. Wrong voltage or frequency
3. Improper connections in lifting motor or pushbutton
station
4. Brake does not release
5. Faulty reversing contactor
Hook does not stop promptly
1. Lifting motor overloaded
2. Brake not holding
Hook moves in wrong direction
1. Three phase reversal
2. Improper connections
Lifting motor hesitates to lift when energized
1. Lifting motor overloaded
2. Motor brake requires adjustment
3. Worn overload limiting clutch
4. Low voltage
5. Faulty SINPAC ® starting switch or start capacitor
(single phase lifting motors only)
Hook raises but will not lower
1. "DOWN" circuit open
2. Broken conductor in pushbutton cable
3. Faulty reversing contactor
Hook lowers but will not raise
1. Lifting motor overloaded
2. Low voltage
3. "UP" circuit open
4. Broken conductor in pushbutton cable
5. Faulty reversing contactor
6. Faulty capacitor (single phase lifting motor only)
7. Worn overload limiting clutch
8. Loose screw clamps
Motor overheats
1. Excessive load
2. Low voltage
3. Extreme external heating
4. Frequent starting or reversing
5. Brake dragging
Lack of proper lifting speed
1. Lifting motor overloaded
2. Brake dragging
3 Low voltage
4. Overload limiting clutch intermittently slipping
For more information contact: Sievert Crane and Hoist, (708) 771-1600, parts@sievertelectric.com, www.sievertcrane.com
Failure to follow proper lockout/tagout procedures may
present the danger of electrical shock.
Disconnect power and lockout/tagout disconnecting
means before removing cover or servicing this
equipment.
1. Check adjustment (See LIMIT SWITCH ADJUSTMENT, page 8). Check connections against wiring diagram.
Tighten loose connections or replace.
2. Check for stripped threads or bent nut guide.
3. Remove electrical cover and check reversing contactor.
1. Check circuit breakers, switches and connections in power supply lines.
2. Check voltage and frequency of power supply against the rating on the nameplate of the motor.
3. Check all connections at line connectors and on terminal block. Check terminal block on dual voltage lifting motors
for proper voltage connections.
4. Check connections to the solenoid coil. Check for open or short circuit. Check for proper adjustment (See BRAKE
ADJUSTMENT, page 8).
5. Check coils for open or short circuit. Check all connections in control circuit. Check for burned contacts.
Replace as needed.
1. Reduce load to within rated capacity of lifting motor.
2. Check brake adjustment (See BRAKE ADJUSTMENT, page 8). It may be necessary to replace discs.
1. Reverse any two wires (except the green ground wire) at the power source (See INSTALLATION, page 4).
2. Check all connections against wiring diagram.
1. Reduce load within rated capacity of lifting motor.
2. Check motor brake adjustment (See BRAKE ADJUSTMENT, page 8).
3. Replace clutch.
4. 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 reversing contactor while lifting a load.
5. Replace faulty component.
1. Check circuit for loose connections. Check "DOWN" limit switch for malfunction.
2. Check each conductor in the cable. If one is broken, replace entire cable.
3. Check coils for open or short circuit. Check all connections in control circuit. Check for burned contacts.
Replace as needed.
1. Reduce load to within rated capacity of lifting motor.
2. 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 reversing contactor while lifting a load.
3. Check circuit for loose connections. Check "UP" limit switch for malfunction.
4. Check each conductor in the cable. If one is broken, replace entire cable.
5. Check coils for open or short circuit, check all connections in control circuit. Check for burned contacts.
Replace as needed.
6. Check starting capacitor on motor. Replace if necessary.
7. Replace overload clutch assembly.
8. Ensure that screw clamps are tightened on the terminal blocks and reversing contactor.
1. Reduce load to within rated capacity of lifting motor.
2. 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 reversing contactor while lifting a load.
3. As the ambient temperature rises towards the 130°F limitation of the unit, frequency of the lifting motor operation
must be limited to avoid overheating of the motor. See ADVERSE ENVIRONMENTAL CONDITIONS, page 3.
4. Excessive inching, jogging or reversing should be avoided since this type of operation will drastically shorten the life
of motor, contactor and brake.
5. Check brake adjustment (See BRAKE ADJUSTMENT, page 8).
1. Reduce load to within rated capacity of lifting motor.
2. Check for proper brake adjustment or other defects.
3. Ensure that the voltage at the reversing contactor is within ±10% of the nominal voltage while lifting a load.
4. Replace overload clutch assembly.
13
Country Club Road
P.O. Box 779
Wadesboro, NC 28170 USA
TEL: (800) 477-5003
FAX: (800) 374-6853
TO AVOID INJURY:
––– Remedy–––