Trouble Shooting - Yale HOISTS YEL Series Operating, Maintenance & Parts Manual

Country Club Road
P.O. Box 779
Wadesboro, NC 28170 USA
TEL: (800) 477-5003
FAX: (800) 374-6853

TROUBLE SHOOTING

Always disconnect unit from the power supply system before
removing hoist 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. Hoist reversing contactor malfunctioning
Hoist does not respond to pushbutton
1. Power failure in supply lines
2. Wrong voltage or frequency
3. Improper connections in hoist or pushbutton
station
4. Brake does not release
5. Faulty hoist reversing contactor
Hook does not stop promptly
1. Hoist overloaded
2. Brake not holding
Hook moves in wrong direction
1. Three phase reversal
2. Improper connections
Hoist hesitates to lift when energized
1. Hoist overloaded
2. Motor brake requires adjustment
3. Worn overload limiting clutch
4. Low voltage
5. Faulty SINPAC ® starting switch or start capacitor
(single phase hoists only)
Hook raises but will not lower
1. "DOWN" circuit open
2. Broken conductor in pushbutton cable
3. Faulty hoist reversing contactor
4. Loose screw clamps
Hook lowers but will not raise
1. Hoist overloaded
2. Low voltage
3. "UP" circuit open
4. Broken conductor in pushbutton cable
5. Faulty hoist reversing contactor
6. Faulty capacitor (single phase hoist 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
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 hoists 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 9).
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 hoist.
2. Check brake adjustment (See BRAKE ADJUSTMENT, page 9). It may be necessary to replace discs.
1. Reverse any two wires (except the green ground wire) at the power source (See INSTALLATION 3c, page 5).
2. Check all connections against wiring diagram.
1. Reduce load within rated capacity of hoist.
2. Check motor brake adjustment (See BRAKE ADJUSTMENT, page 9).
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 hoist 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.
4. Ensure that screw clamps are tightened on the terminal blocks and reversing contactor.
1. Reduce load to within rated capacity of hoist.
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 hoist 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 hoist.
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 hoist reversing contactor while lifting a load.
3. As the ambient temperature rises towards the 130°F limitation of the unit, frequency of the hoist operation must be
limited to avoid overheating of the motor. See ADVERSE ENVIRONMENTAL CONDITIONS, page 4.
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 9).
12
TO AVOID INJURY:
––– Remedy–––