5
BREAKDOWN MAINTENANCE
5.1.9
When abnormal noise is generated from the motor
The motor generates an abnormal acoustic noise.
motor immediately
5.1 Troubleshooting
60
YES
Is the
before a stop?
NO
What kind of sound?
Chattering
Rumbling
Rasping
Growling
Screeching
Whining
Hissing
Rustling
Resonant sound
Others
The motor is faulty.
Replace it with a substitute or
return it to the factory to repair.
Review G100 (Pr.10) to G110 (Pr.12)
that are related to the DC injection brake
operation.
Mechanical cause
Check installing condition of
shafts, bearings, and fan motors.
Normal
Wind noise from fans
Normal
Operation sound generated when a load is applied
Motor stalling
Review the stall prevention level.
Normal magnetic sound
Increase the carrier frequency.
Select SOFT-PWM.
SOFT-PWM is selected.
When the sound is disturbing, stop
SOFT-PWM and increase the
carrier frequency.
10-A
Resonance phenomenon