The UMS monitoring and control system of a ship has recently started to give false alarms and incorrect data printouts. (a) State, with reasons, the possible causes.(5) (b) State, with reasons, the action that should be taken to ensure continued safe operation of the vessel.(5)
(a) Possible causes of false alarms and incorrect printouts (5)
Faulty sensors or detectors – damaged, contaminated, or poorly calibrated sensors may transmit incorrect signals.
Electrical faults – loose connections, faulty wiring, or poor earthing can generate spurious signals.
Software or system malfunction – corrupted programs or configuration errors may cause false alarms.
Power supply fluctuations – unstable or interrupted supply to the UMS panels can disrupt normal operation.
Interference or grounding issues – electromagnetic interference or improper shielding may distort signals.
(b) Actions to ensure continued safe operation (5)
Inform the Chief Engineer immediately – so temporary operating procedures can be agreed.
Revert to manual watchkeeping – maintain continuous manned watch in the machinery space until reliability is restored.
Verify critical alarms locally – confirm actual machinery status by direct readings (gauges, sounding tanks, manual inspections).
Arrange inspection, testing, and repair – identify and correct the fault, including calibration and sensor replacement if required.
Record the defect and corrective action – enter details in the defect log, maintenance records, and inform the bridge for operational awareness.
