Unreliable component causes a DP undesired event
Comments from the report:
Investigation found that a 24v bridge rectifier supplying voltage to the main generator switchboard breakers 1 and 2 had burned out. The age and quality of the rectifier was thought to be the main reason for failure. Planned maintenance routines were updated and shared with the fleet. It was recognised that the system was vulnerable due to a single 24v bridge rectifier supplying the entire port switchboard.
Considerations of the IMCA Marine DP Committee from the above event:
The vessel validated that it could maintain position following the worst-case failure of a complete switchboard. Though redundancy is a must in DP 2/3 designs, components quality may impact the likelihood of such DP events occurring.
DP Event
Published: 25 February 2020
Download: 
IMCA DPE 01/20
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