Alarm guide · Yaskawa · Updated October 2026
Yaskawa A.720 alarm: continuous overload
Yaskawa A.720 is a continuous overload alarm: the motor ran above its rated torque for too long. Check the load, brake and mechanism, then the motor.
By Suresh Sankaran, founder of Star Automations, servo motor repair since 1998.
What the alarm means
The drive stopped the motor because it was carrying more load than allowed for too long. Alarm numbers and wording can differ between series, so confirm with the manual for your unit.
Common causes
- Load or duty above the motor rating
- Brake not released
- Mechanical friction or a jam
- Wrong gains causing vibration
- Winding or bearing fault
Safe first checks
General guidance only. Follow the drive manual and your site's electrical safety rules. Power off, and let the DC bus discharge, before touching connectors.
- Note the exact alarm code and when it appears: at power-up, at start, or under load.
- Power off and turn the shaft by hand if safe: it should turn smoothly.
- Check the motor cable, encoder cable and connectors for damage and loose contacts.
- Check what changed recently: load, speed, settings, cables or a replaced part.
When to send it for repair
If the mechanism is free and the load is normal, send the motor for inspection.
We test every motor on our Universal Servo Motor Repair Equipment, which reads and aligns the feedback and runs the motor under load without the original drive.
See Yaskawa servo motor repair, Yaskawa encoder repair and Yaskawa servo drive repair.
Questions
What is the difference between A.710 and A.720?
A.710 is an instantaneous overload (a heavy short load). A.720 is a continuous overload (a long moderate overload).
How long does repair take?
Emergency repair is done the same day where the fault and parts allow, urgent in 3 working days and standard in 7 working days, counted from when the unit reaches our bench and the quote is approved. Every unit returns with a printed test report.
Can I get an exchange unit?
If we hold a matching unit, Servo Swap ships a tested exchange unit while yours is repaired. Mark "line down" on the request form and add the part number.