Good practice following system self-test alarm
- DP Event
- Published on 29 May 2018
- Generated on 14 November 2026
- DPE 02/18
- 1 minute read
Observation
The decision was made to replace a serial interface module with a new one, dive control was requested to recover the bell whilst this took place.
Comments
The error was traced to a serial interface module for DP Controller A and confirmed that the red error lamp on this module was illuminated.
Whilst indicating an error, the module was still performing correctly in so far as there was no effect with its data feeds.
The decision was made to replace the module with a new one, dive control was requested to recover the bell to surface and hold it there whilst replacement was carried out.
Considerations
- The actions taken were all in accordance with good practice.
- 40m water depth only provides for a small envelope for seabed based position reference systems (PRS).
- In these depths of water, it is advisable to make use of surface based PRS, in this instance DGNSS was used.
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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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