DON I/O Failed Off?

If so did you check all the possible causes?

The DON input or the drive run
relay contact has failed off. The
run relay on the drive turns on
the DON input (Drive ON)
indicating that the regulator is
released and the drive is
controlling the motor.

Possible Cause/Suggested Fix

• Loss of voltage on terminal CS.
• MC contact in series with the drive
run relay opened.
• The drive faulted on start and
dropped the run relay. Check the
drive fault log.
• Faulty run relay on the drive.
• Faulty DON input on the controller.
Replace the DON input chip.

• The run relay in the drive is not pro-
grammed properly. Check the

default drive setup for the Configure
C0 parameters.


Since its an intermittent issue maybe its a relay issue.