Check of the UPS led to loss of power

  • DP Event
  • Published on 2 November 2017
  • Generated on 11 September 2026
  • DPE 04/17
  • 1 minute read

Incident

Maintenance needs to be carefully managed during DP operations and avoided whilst the vessel is operating on DP.

DPE 17.04 – Check of the UPS led to loss of power – DP Incident – Flowchart

Comments

  • At approximately 15:55, the ETO came to the bridge and asked the Senior DPO permission to enter the electronics room to check the UPS batteries.

  • The SDPO gave permission, not knowing the detailed work scope of the ETO.

Considerations

  • Both planned and unplanned work on DP equipment should be subject to a permit to work system.

  • Maintenance routines need to be carefully managed during DP operations and planned maintenance of any DP equipment should be avoided whilst the vessel is operating on DP.

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The case studies and observations above have been compiled from information received by IMCA. All vessel, client, and operational data has been removed from the narrative to ensure anonymity. Case studies are not intended as guidance on the safe conduct of operations, but rather to assist vessel managers, DP operators, and technical crew.

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