Page 8 - 2021 - Q3 - Minerva in Focus
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SAFETY & SECURITY  Safety Digest:

           Getting your wires crossed

                                                                           Figure: Heat damaged electrical cabling
                                                                           Source: Marine Accident Investigation
                                                                           Branch (MAIB)

           The Incident                                        On the return of the overhauled starter motor to the vessel, the
           [occurred onboard a vessel of another company]      relief chief engineer carried out the re-installation and connected
                                                               the power cables to the positive and negative terminals of the
           A vessel’s number 2 diesel generator was experiencing starting dif-  starter motor. As the generator was started, smoke and a small fire
           ficulties. After conducting some tests, the chief engineer decided   appeared from the starter motor and surrounding area.
           to remove the starter motor and send it ashore for an overhaul.   A subsequent examination of the heat-damaged starter motor and
           While the starter motor was being overhauled, the vessel re-  cabling (see figure) identified that the electrical wiring had been
           mained alongside, and a crew change occurred, including the   incorrectly connected. On that particular engine model, some of
           arrival of the relief chief engineer. The off-going chief engineer   the positive side cablings were coloured black instead of the more
           referred to the removal of the starter motor in general terms in   usual red. This had not been mentioned in the handover notes or
           his handover notes.                                 noticed during the reconnection.

           Lessons Learned

           •    Damage sustained to machinery after a repair or overhaul can be due to poor communication, such as when the re-installation
                is carried out by a different person to the one who disassembled the piece of machinery. It is all too easy to assume that your
                opposite number understands what is involved and what the correct re-build process is. But what if they do not? If you are
                unable to discuss the reassembly in person, ensure detailed notes, photographs, and references to the manufacturer’s manual
                are provided. This will potentially save costly embarrassment or, worse, a major fire or other disaster.
           •      Arriving on board to find a pile of parts from your opposite number and limited handover notes, it may be tempting to pick up
                the spanners and quickly get on with the reassembly. Does the benefit of quickly putting something back together outweigh the
                potential for a catastrophic failure if assembled incorrectly? Time spent on reading instructions or getting assistance could be
                time well spent.

          6  MINERVA IN FOCUS – ISSUE 17 / Q3 2021                   Source: Marine Accident Investigation Branch (MAIB)
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