DOCA0095EN

Troubleshooting the PowerPact B Circuit Breaker

Repetitive Tripping

Indication

Probable Cause

Checks or Repairs

SD

The voltage of the power supply to the MN undervoltage release is too low or subject to significant variations.

Check the power supply for the release. For example, a supply powering motors with high-power ratings can be unstable. If necessary, connect the release to a clean or stable supply.

The power supply to an MX shunt trip is applied unintentionally.

Compare the release connection with the installation diagram to make sure that it is correct.

Circuit Breaker Does Not Close

Indication

Probable Cause

Checks or Repairs

SD

MX shunt trip energized.

MN undervoltage release not energized.

Compare the release connection with the installation diagram to make sure that it is correct.

QR Code is a registered trademark of DENSO WAVE INCORPORATED in Japan and other countries.

Was this helpful?