Servo Drive Throwing Alarms — What the Codes Usually Mean
Overcurrent-class alarms (FANUC alarm 8/12, Mitsubishi AL.32, Yaskawa A.10) usually mean a failed power stage inside the amplifier — or a shorted motor/cable that will kill the next amplifier too. A proper bench evaluation isolates which, before you spend anything. Send the alarm code with your unit; it cuts diagnosis time dramatically.
What's usually behind it
Failed IGBT / IPM power module
The classic servo amplifier failure. The intelligent power module shorts, the drive faults instantly at enable or trips the breaker. Replaced with new components, gate drive verified, then powered testing.
DC bus capacitor aging
Aged bus capacitors cause undervoltage alarms, faults under load, and eventually take the power stage with them. Every drive repair we do includes recapping aged electrolytics.
Shorted motor or cable
A motor winding or cable short presents as an amplifier overcurrent. If our evaluation shows your amplifier is healthy, you pay nothing — and you've just saved the next amplifier from the same fate.
Encoder / feedback faults
Feedback alarms can live in the amplifier's encoder interface or in the motor encoder. Bench evaluation tells you which side of the connector the problem is on.
Repairs that fix this
FANUC
Free evaluationFANUC Servo Amplifier Repair
Alarm 8, 12, or a dead amp on a FANUC machine? Free bench evaluation, firm quote before any work — most repairs land between $650 and $1,500.
3–5 business days in lab · Free evaluation →
Mitsubishi Electric
Free evaluationMitsubishi Servo Amplifier Repair
MR-J2S amps run half the CNC world and fail the same way — a blown IPM. Free evaluation; typical repairs $450–$950.
3–5 business days in lab · Free evaluation →
Yaskawa
Free evaluationYaskawa Servo Repair
Sigma-series servopacks from legacy SGD to Sigma-5 — free evaluation, typical repairs $400–$900.
3–5 business days in lab · Free evaluation →
Indramat / Bosch Rexroth
Free evaluationIndramat / Rexroth Drive Repair
Indramat drives outlived their OEM support decades ago. Free evaluation, typical repairs $600–$1,200.
3–5 business days in lab · Free evaluation →
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