Steering Control System (SCS)

Verify potentiometer kit replacement intervals: RFC/RFU systems with sliding contact require replacement every 5 years maximum. RFC360-D Hall sensor versions have 10-year service life minimum. Test analog output signals (±12Vdc, ±15Vdc) from feedback units for noise and drift; confirm no mechanical wear in uni-ball links or belt drives on RFU/RFB units.

Verify port-to-starboard rudder movement completes within 28-38 seconds per SOLAS requirements. Test RCU servo boxes (RCU10-440, RCU20-440, RCW10-440) for proportional/bang-bang control accuracy. Confirm power supply voltages at KSA control boards are stable (+/-12Vdc, +/-15Vdc, 100Vac). Check no hydraulic lock alarms on torque motors; verify coupling condition.

Verify WMS (Work Mode Station) PLC firmware version matches documented baseline. Test RSR relay expansion boxes function correctly in multi-rudder systems. Confirm backup power supply (SAB.10/SAB10-230) voltage levels and capacitor condition. Verify hot standby redundancy switches operate without glitches; test fail-over response time.

Test RIB511 and RIF511 rudder angle indicators for calibration accuracy against actual rudder position sensors. Verify analog output (1-0.1mA) continuity from indicators to autopilot control panels. Confirm SEM300 TFT display brightness (800 cd/m²) is within specification and visible from all bridge positions. Check all 4 control panel connections have consistent readouts; verify alarm annunciation.

Identify installed steering gear brand (Mitsubishi, Kawasaki, ABB, Hatlapa, Hitachi) and confirm correct RCU/ACU model variant is installed. Verify hydraulic pump configuration matches system design: 3-pump systems use RCU10/RCW10 models, 4-pump LNG systems use RCU20-440. Test proportional vs. bang-bang control mode operation per gear manufacturer specifications. Inspect hydraulic hose condition and pressure relief valve settings.