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9. Troubleshooting
Common
If any abnormal condition occurs, refer to Table 9-1, 9-2 and promptly take appropriate measures.
If these actions do not remedy the issue, immediately contact the nearest authorized service station.
Table 9-1 Troubleshooting
Problem
Cause
Correction
The motor will not operate under no load
Power failure
Contact the electric power company.
Defective electric circuit
Check the circuit.
Blown fuse
Replace the fuse.
Protective device is engaged
Fix the problem and recover.
Load locking
Check the load and safety device.
Poor switch contact
Adjust the contact unit.
Motor stator coil disconnect
Confer with authorized service station.
Bearing damage
Confer with authorized service station.
3-phase is functioning as single-phase
Check the power supply with a voltmeter.
Check the motor, transformer coil, contactor,
fuse, etc. and repair or replace them.
Friction surface of brake is corroded
Request brake cleaning from authorized
service station.
Incorrect brake gap adjustment
Re-adjust brake gap.
(See P47 – 68)
The motor rotates without a load but the
slow speed shaft does not rotate
Damage to gear unit due to overloading of
gears, etc.
Confer with authorized service station.
The slo
w speed shaf
t tur
ns without a load
W
hen a load is applied
The switch overheats
Insufficient switch capacity
Replace with specified switch.
Overload
Decrease the load to the specified value.
Fuse tripping
Insufficient fuse capacity
Replace with specified fuse.
Overload
Decrease the load to the specified value.
The speed will not increase and
the motor is overheating
Voltage drop
Contact the electric power company.
Overload
Decrease the load to the specified value.
Short-circuited motor stator coil
Confer with authorized service station.
It stops
The key is not inserted
Insert key.
Bearing burnout
Confer with authorized service station.
Poor adjustment of protection device
Adjust the protection device.
The motor runs in the reverse
direction
Wiring error
Change the connection.
Fuse tripping
The lead wire is short circuited.
Confer with authorized service station.
Poor contact between motor and starter
Make good connection.
Excessive temperature rise
Overload
Decrease the load to the specified value.
Voltage drop or rise
Contact the electric power company.
The ambient temperature is high
Improve the ventilation method.
Damaged bearing
Confer with authorized service station.
Abnormal wear of reducer parts due to
overload, etc.
Confer with authorized service station.
Oil leak
age
Blot or drip of a small amount of
oil or grease at seal section of high
speed or slow speed shaft
Grease applied to the oil seal seeps out at first Wipe off around the oil seal, and observe.
Leakage of oil or grease from high
speed or slow speed shaft section
Damaged oil seal or maybe damaged shaft (or
collar)
Confer with authorized service station.
Leakage of oil/grease from the
contact surfaces of ring gear housing
and casing, etc.
Loose fastener bolts
Tighten fastener bolts correctly.
Leakage of oil/grease into motor
Damage to oil seals, or slinger collar
Confer with authorized service station.
Excessive oil supply
Remove oil.