What the Er.201 alarm means

The drive power-stage hardware detected a current spike beyond the IGBT protection threshold and cut output immediately. This is one of the faults our repair team handles on INOVANCE IRCB500 / IRCB501 + SV660 servo systems — the cause is usually identifiable within the first on-site inspection.

Most common causes

  • Motor cable U/V/W shorted to ground or phase-to-phase
  • Motor winding insulation failure
  • Damaged IGBT module
  • Coolant or oil inside a motor connector
Field note: the first item on this list is what we find most often on real machines. Check it before you go deeper.

Step-by-step field fix

  1. Power off, discharge the DC bus, then megger motor phases to ground
  2. Disconnect the motor and power the drive alone — recurring Er.201 means a dead power stage
  3. Open and dry contaminated connectors
  4. Inspect the cable for pinch damage along the robot dress pack
  5. Replace the failed component and re-test at low speed
Safety first: never bypass safety circuits or force contactors closed. If the alarm involves E-stop chains, brakes or drive power, and you are not a trained robot technician, contact a professional — wrong moves here can cost you a robot or an injury.

Still stuck? Get an engineer on the phone — right now

Tell us the alarm code, the robot model and what was happening when the alarm came up. Our engineers run these diagnostics every day, and remote diagnosis by phone or video call is free.

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Hotline: +86-20-39029800 · WhatsApp: +86-188-1886-2860

Related Drive & Power Stage alarms

Er.210 — Motor Overload Er.400 — Main Circuit Overvoltage Er.410 — Main Circuit Undervoltage Er.610 — Drive Overload (I2t) Er.920 — Regenerative Overload
Other brands: we also keep field-fix libraries for EFORT · JAKA · AUBO and more — see the complete alarm code hub.

Frequently asked questions

QWhat does the INOVANCE Er.201 alarm mean?

The drive power-stage hardware detected a current spike beyond the IGBT protection threshold and cut output immediately. In field practice it belongs to the drive & power stage family of faults.

QCan I clear a INOVANCE Er.201 alarm myself?

Sometimes. Work through the step-by-step checks on this page — the first listed cause is what we find most often in the field. If the alarm returns after two attempts, or the fault involves power, brakes or safety circuits, stop and call a qualified robot service engineer.

QHow fast can a Henghuan engineer help?

On-site response in the Pearl River Delta within 30 minutes to 3 hours, across mainland China in 1-3 business days, and worldwide within 2-5 business days. Remote diagnosis by phone/WhatsApp/video is available immediately.

Written by the Henghuan Robotics repair team from field service experience. Alarm descriptions are our own summary for troubleshooting reference and may vary by controller and software version — when in doubt, check your INOVANCE documentation or contact us. Henghuan is an independent service provider, not affiliated with or endorsed by INOVANCE.