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  1. Home
  2. Fault Codes
  3. Yaskawa SGDH
  4. A.40
A.40Alarm · Power section

Yaskawa SGDH A.40: Overvoltage

What A.40 means

The main circuit DC voltage went too high.

Symptoms

Alarm during deceleration or with a high supply voltage.

Is it repairable?

Often settings or resistor related; repairable when the voltage sensing has failed.

Common causes

  • Deceleration too fast for the load
  • Regenerative resistor too small or failed
  • Supply voltage too high

Safe checks

  1. 1Note whether the alarm happens while braking
  2. 2Check the regenerative resistor
  3. 3Measure the supply voltage

Drives hold dangerous voltage after power-off. Checks should only be done by qualified personnel, with power isolated and the DC link discharged.

Reviewed by AutomIQ repair technicians. Code and name from the Yaskawa SGDH SERVOPACK manual.

Related Yaskawa SGDH faults

  • A.10Overcurrent or Heat Sink Overheated
  • A.30Regeneration Error Detected
  • A.41Undervoltage
  • A.71Overload: High Load
  • A.81Encoder Backup Error
  • A.C9Encoder Communications Error
All 49 Yaskawa SGDH codes

Still showing A.40?

SGDH SERVOPACK showing an alarm?

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