MFG-III Marine Optic Gyro Compass

Common issues

• Follow-up/repeater synchronization errors between the master gyro and repeaters
• Settling/drift errors after start-up, especially following a power interruption
• Heading error from mechanical wear in gimbal/rotor bearings or fibre-optic sensor drift, depending on gyro technology
• Power supply instability causing spurious alarms or resets
• Corrosion or moisture ingress at repeater and junction box connections
• Interface faults with connected systems such as autopilot, radar, ECDIS, or AIS due to data output errors

Inspection checklist

• Compare gyro heading against the magnetic compass and GPS course over ground periodically
• Check settling time and accuracy after each start-up against the manufacturer's specification
• Inspect repeater compasses for correct synchronization with the master
• Check power supply voltage and backup/UPS function
• Inspect cabling and connectors to interfaced navigation equipment (autopilot, ECDIS, radar, VDR)
• Verify alarm functions (power failure, heading error) operate correctly
• Confirm latitude/speed error correction settings are correctly entered
• Check housing and mounting for corrosion and secure fixing

Service intervals

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Repeater compass unit as fitted
• Power supply module/UPS battery
• Interface/output cards for connected navigation systems
• Connecting cables and connectors

Safety

• Loss of heading reference affects autopilot and collision-avoidance systems - always cross-check against the magnetic compass, especially before entering restricted waters
• Electrical hazard when servicing power supply units - isolate before opening
• A wrongly synchronized repeater can feed an incorrect heading to radar/ECDIS and the autopilot without an obvious alarm - verify repeater agreement, not just the master display

Class survey

Note on data quality: the order data lists this item's type as 'X-Band Radar (9 GHz)' under category 'Radar & ECDIS', but the product name ('Marine Optic Gyro Compass') and the DNV MED certificate reference indicate this is actually a marine fibre-optic gyro compass, not a radar - the catalogue type/category field appears to be a data error and should be corrected separately. This content addresses the gyro compass as the actual product. As a heading reference device, class/PSC will check the SOLAS-required heading comparison routine, MED type approval certificate validity, and correct interfacing with the autopilot and other navigation equipment at survey.