A retrofitted capacitor caused a bow thruster frequency drive to overheat
- DP Event
- Published on 27 February 2018
- Generated on 22 June 2025
- DPE 01/18
- 1 minute read
Observation
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Vessel operators should ensure that a robust management of change procedure is followed.

Comments
A wrongly installed extra capacitor at the bow thruster frequency drive caused overheating of this equipment.
The extra capacitor was installed by the electrical designer and supplier of this equipment. It was also removed following consultation with the original equipment supplier.
Considerations
- Further investigation should be initiated, including the supplier/manufacturer, as to why the extra capacitor was installed and whether another solution is required to ensure the thrusters function correctly in the future.
- Vessel operators should ensure that a robust management of change procedure is followed.
- A good response and sequence of events taken to minimise escalation.
- A good choice and use of position reference systems is noted.
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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.
IMCA makes every effort to ensure both the accuracy and reliability of the information, but it is not liable for any guidance and/or recommendation and/or statement herein contained.
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