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6.2 Troubleshooting for faults in general
Fault
Check points
Treatment
Motor doesn’t run
Check connection of power supply to
terminals L1/R, L2/S, L3/T?
Input power supply
Supply power again after power firstly
interrupted.
Verify voltage class of power supply
Tighten screws for terminals
Check voltage output from output
terminals U/T1, V/T2, W/T3.
Supply power again after power firstly
interrupted.
Check motor is not blocked due to
load over-large
Decrease load to make motor running
available
Check fault of inverters
Check wiring and correct it if necessary
in accordance with reference for fault.
Check fwd/rev run reference
achieved
Check input of Analog frequency
setting
Verify wiring for analog frequency input
signal
Verify frequency input set voltage
Verify operation mode setting
Controlled by digital operator.
Contrary rotation
direction of motor
Check wiring for output terminals
U/T1, V/T2, W/T3
Match correctly with terminals U/T1,
V/T2, W/T3 of motor
Check wiring for FWD/REV run
Verify wiring and correct if necessary
Velocity variation
unavailable for
motor running
Check wiring for analog frequency
input
Verify wiring and correct if necessary
Check operation mode setting
Check and verify operation mode setting
Check motor is free from overload.
Decrease load
Motor running
speed over high or
over low
Check specification(number of poles
and voltage)of motor
Confirm specification of motor
Check gear proportion
Confirm gear proportion
Check Max output frequency setting Confirm Max output frequency setting
Check voltage is not dropping at
motor side
Verify V/F curve setting
Speed variation
fault during motor
running
Check motor overload
Decrease load
Check load is not in sharp variation
Decrease load variation
Increase capacity of inverter and motor.
Check no phase failure occur to
power supply
For single phase mode, fix AC reactor to
power supply side
Verify wiring for Three phase mode.
