c
Inverter: DC link current alarm (M axis)
Fanuc · Series 30i CNC
What does c mean?
An abnormal current condition has been detected in the DC link for the M-axis. This can be caused by short-circuits or ground faults in power leads or motor windings, an incorrect motor ID setting, or a failure of the motor or SVM itself.
Common Causes
- Short-circuit between power lead phases or ground fault in them.
- Short-circuit between motor winding phases or ground fault in them.
- Incorrect motor ID setting.
- SVM failure.
- Motor failure.
Repair Steps
- 1
Measure insulation resistance between power lead phases (U-V, V-W, U-W) and to ground for the M-axis.
- 2
Measure insulation resistance between motor winding phases (U-V, V-W, U-W) and to motor frame ground for the M-axis.
- 3
Verify the motor ID setting in the SVM parameters matches the installed M-axis motor.
- 4
Visually inspect power leads for the M-axis for signs of short-circuits or damaged insulation.
Verified technical data. Last updated: March 2026
Source: Fanuc Series 30i CNC