SV0438Servo alarm · Servo amplifier (SVM)Usually repairable
Fanuc αi SV0438: Inverter Motor Current Alarm
Also shown as: SVM display b / C / d; 16i/18i/21i/0i: 438
What SV0438 means
The servo amplifier detected abnormal motor current. Shown on the amplifier as b, c or d for the L, M or N axis.
Symptoms
Alarm at enable or during acceleration.
Is it repairable?
Yes, when the amplifier or motor is at fault.
Common causes
- Motor winding short or ground fault
- Damaged power cable
- Wrong servo parameters
- Faulty current detection in the amplifier
Safe checks
- 1Megger the motor and cable
- 2Compare phase-to-phase winding resistance
- 3Check that servo parameters match the motor
Drives hold dangerous voltage after power-off. Checks should only be done by qualified personnel, with power isolated and the DC link discharged.
Reviewed by AutomIQ repair technicians. Code and name from the FANUC αi series Maintenance Manual.
Related Fanuc αi faults
- SV0368Serial data error (built-in)
- SV0401V ready off
- SV0433DC link undervoltage
- SV0436Soft thermal (OVC)
- SV0442DC link precharge failure
- SV0443cooling fan stopped