What the 1801 alarm means

The EC2-S controller's safety unit detected a major fault in the safety chain; all servo power is cut until the chain is healthy again. Codes 1800-1999 are major alarms that stop the whole system. This is one of the faults our repair team handles on EFORT EC2-S controller + TSINO drives systems — the cause is usually identifiable within the first on-site inspection.

Most common causes

  • Dual-channel E-stop wiring mismatch (one channel open)
  • Safety relay contacts welded or failed
  • Gate switch circuit fault
  • Safety I/O module error
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. Check both E-stop channels for simultaneous operation
  2. Test the safety relays with a meter
  3. Verify gate switches close on both channels
  4. Inspect the safety I/O module status LEDs
  5. Reset the safety unit only after the wiring fault is fixed
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 Safety Chain & E-Stop alarms

1802 — Emergency Stop Active (EC2-S) 1810 — Enable Switch Fault (EC2-S)
Other brands: we also keep field-fix libraries for JAKA · AUBO · ROKAE and more — see the complete alarm code hub.

Frequently asked questions

QWhat does the EFORT 1801 alarm mean?

The EC2-S controller's safety unit detected a major fault in the safety chain; all servo power is cut until the chain is healthy again. Codes 1800-1999 are major alarms that stop the whole system. In field practice it belongs to the safety chain & e-stop family of faults.

QCan I clear a EFORT 1801 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 EFORT documentation or contact us. Henghuan is an independent service provider, not affiliated with or endorsed by EFORT.