Accidental breaker trip – DP undesired event

Comments from the Report:

The vessel was experiencing heavy rolling and pitching.  The watch keeping engineer lost his balance and his hand made contact with the No. 2 shaft generator breaker push button, thus opening the breaker and causing the loss of power.  The vessel has installed transparent covers over vulnerable breaker push buttons to avoid re-occurrence.

Considerations of the IMCA Marine DP Committee from the Above Event:

  • Although the incident could have been avoided by better protecting the breaker push-button, the DP system responded as designed.
  • Most regulatory authorities require covers to be fitted on emergency stops which have the potential to impact operations.
  • The vessel could have moved clear while still on Automatic DP, instead of changing to joystick control.
  • With only one generator on-line on each bus, failure of one may cause a partial black-out. It is assumed that this was included in the operational philosophy and activity specific planning.