What the A.720 alarm means

The motor ran continuously above rated torque; unlike A.710 this builds up slowly and usually points at a systemic mechanical or setup problem rather than a single collision. This is one of the faults our repair team handles on Yaskawa DX100 / DX200 / YRC1000 systems — the cause is usually identifiable within the first on-site inspection.

Most common causes

  • Payload setting higher or lower than the real tool weight
  • Unbalanced axis (balancer pressure wrong on J2/J3)
  • Worn reducer creating drag
  • Cabinet ambient temperature too high
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. Confirm the payload/inertia parameters match the actual end effector
  2. Check gas balancer pressure where applicable
  3. Listen for reducer noise and check axis backdrivability with power off
  4. Lower ambient temperature or improve cabinet ventilation
  5. If current remains high with no load, test the motor and SERVOPACK
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

A.100 — Overcurrent or Heat Sink Overheated (SERVOPACK) A.320 — Regenerative Overload A.400 — Overvoltage — Main Circuit DC Voltage Too High A.410 — Undervoltage — Main Circuit DC Voltage Too Low A.710 — Overload — High Load (Stall-level Torque) A.7A0 — Heat Sink Overheated (>100 degC)
Other brands: we also keep field-fix libraries for Universal Robots · Kawasaki · Staubli and more — see the complete alarm code hub.

Frequently asked questions

QWhat does the Yaskawa A.720 alarm mean?

The motor ran continuously above rated torque; unlike A.710 this builds up slowly and usually points at a systemic mechanical or setup problem rather than a single collision. In field practice it belongs to the drive & power stage family of faults.

QCan I clear a Yaskawa A.720 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 Yaskawa documentation or contact us. Henghuan is an independent service provider, not affiliated with or endorsed by Yaskawa.