SHIP ELECTRICAL POWER SYSTEM

POWER GENERATION

Main Bus Voltage

MAIN BUS A440 V / 60 Hz

MAIN BUS BDEAD

EMERG BUSDEAD

Diesel Generator No.1

DG-1 · 1500 kW · 440 V ONLINE

Load

850 kW

Load %

57%

Voltage

440 V

Freq

60.0 Hz

Current

1113 A

P.F.

0.93

Diesel Generator No.2

DG-2 · 1500 kW · 440 V STANDBY

Load

— kW

Load %

—%

Voltage

— V

Freq

— Hz

Current

— A

P.F.

—

Bus Tie Breaker

Paralleling A and B bus — check sync before closing

SINGLE LINE DIAGRAM — MAIN SWITCHBOARD (MSB)

ALARM MANAGEMENT SYSTEM

Blackout: all main power lost · E/G auto-start required

CLICK ALARM TO ACKNOWLEDGE

LOAD MANAGEMENT — TOTAL LOAD

BUS A LOAD

850 kW

BUS B LOAD

0 kW

TOTAL

850 kW

SCENARIO

NORMAL OPERATIONS

DG-1 online feeding Bus A. DG-2 on standby. Loads within limits. Monitor insulation resistance and load balance.

EARTH FAULT DETECTION (IEC 60092)

INSULATION MONITOR

HEALTHY

IT system — resistance to earth

Insulation Resistance (MΩ)

Earth Fault Locator

No fault detected

System Notes (IEC 60092-302)

Ships use IT (Isolated Terra) earthing system. First earth fault does not trip supply but must be located. Second earth fault causes short circuit — find first fault quickly.

DIESEL GENERATORS — DETAIL VIEW

GENERATOR CONTROLS

DG-1 — 1500 kW · 440 V · 60 Hz

StatusONLINE

Load850 kW

Load %57%

Voltage440 V

Frequency60.0 Hz

Current1113 A

Power Factor0.93

Oil Pressure4.2 bar

Coolant Temp78 °C

Run Hours4842 h

DG-2 — 1500 kW · 440 V · 60 Hz

StatusSTANDBY

Load— kW

Load %—%

Voltage— V

Frequency— Hz

Current— A

Power Factor—

Oil Pressure— bar

Coolant Temp— °C

Run Hours3201 h

MAIN SWITCHBOARD — SINGLE LINE DIAGRAM

MSB PANEL LINEUP

INCOMING BREAKERS

DG-1 Incoming ACB

DG-2 Incoming ACB

Shore Power ACB

BUS A — FEEDER BREAKERS

Propulsion Motor 1

Bow Thruster

Cargo Cranes

HVAC Compressors

Fire Pumps (Ess)

BUS B — FEEDER BREAKERS

Propulsion Motor 2

Steering Gear 1

Steering Gear 2

Ballast Pumps

BUS TIE — PARALLELING & SYNCHRONISING

BUS TIE CONTROLS

SYNCHRONISING CHECK

Bus A Voltage440 V

Bus B Voltage— V

Voltage Diff—

Bus A Freq60.0 Hz

Bus B Freq— Hz

Freq Diff—

Phase Angle—

Sync StatusNOT READY

BUS TIE BREAKER

Closes Bus A to Bus B. Both buses share all load. Only close when buses are in sync (ΔV <5%, Δf <0.2 Hz, Δφ <10°).

OPERATING MODES

Split bus preferred for fault containment. Parallel required when transferring load between generators.

LOAD MANAGEMENT — LOAD SHARING & PRIORITISATION

LOAD CONTROLS

TOTAL LOAD SUMMARY

Bus A Load850 kW

Bus A Capacity1500 kW

Bus A Margin43%

Bus B Load0 kW

Bus B Capacity1500 kW

Total System850 kW

PREFERENTIAL TRIP — PRIORITY ORDER

Non-essential loads trip first to preserve essential services when load exceeds generator capacity.

P1 ESSNavigation Equipment

P1 ESSFire Pumps

P1 ESSSteering Gear

P2 PREFHVAC Compressors

P2 PREFBallast Pumps

P3Cargo Cranes

P3Galley Equipment

P4 NONBow Thruster

LOAD SHEDDING

EARTH FAULT DETECTION — IEC 60092-302 IT SYSTEM

INSULATION MONITOR

SYSTEM STATUS

INSULATION MONITOR — MAIN BUS

HEALTHY

IT system — resistance to earth

Bus A Insulation∞ MΩ

Bus B Insulation∞ MΩ

Alarm Threshold50 kΩ

FEEDER INSULATION (MΩ)

FAULT LOCATOR

No fault detected

First earth fault: alarm only — system remains live. Locate and isolate before second fault. Second fault: phase-to-phase via earth — likely blackout.

LOCATOR CONTROLS

PROTECTION RELAY — OVERCURRENT & DIFFERENTIAL

RELAY SETTINGS & STATUS

OVERCURRENT — BUS A

Pickup Current1200 A

Trip Delay0.5 s

Instantaneous8× In

Relay StatusARMED

OVERCURRENT — BUS B

Pickup Current1200 A

Trip Delay0.5 s

Relay StatusARMED

REVERSE POWER — DG1

Trip Setting−5% rated

Delay3 s

StatusARMED

REVERSE POWER — DG2

Trip Setting−5% rated

StatusARMED

UNDERVOLTAGE

Pickup85% Un

Trip Delay1.5 s

StatusARMED

TRIP LOG

No trips recorded.

EMERGENCY GENERATOR — SOLAS Ch.II-1 Reg.43

EMERGENCY GEN CONTROLS

E/G — 250 kW · 440 V · 60 Hz

StatusSTANDBY

Load— kW

Voltage— V

Frequency— Hz

Current— A

Fuel Level87%

Battery Charge100%

Last Test7 days ago

START / STOP

ESSENTIAL SERVICES — AUTO RESTORE

On blackout, E/G auto-starts within 30 s (SOLAS Reg.43). Feeds emergency switchboard only.

Navigation Lights

Steering Gear

Fire Detection

Radio / GMDSS

Emergency Lighting

UPS — UNINTERRUPTIBLE POWER SUPPLY SYSTEMS

UPS STATUS & CONTROLS

UPS-1 — BRIDGE SYSTEMS · 10 kVA

ModeONLINE

Input Voltage440 V

Output Voltage230 V

Battery SOC98%

Load3.2 kVA

Autonomy18 min

StatusHEALTHY

UPS-2 — ENGINE ROOM · 5 kVA

ModeONLINE

Input Voltage440 V

Output Voltage230 V

Battery SOC95%

Load1.8 kVA

Autonomy22 min

StatusHEALTHY

UPS-3 — CARGO CONTROL · 5 kVA

ModeONLINE

Battery SOC92%

Load2.1 kVA

StatusHEALTHY

BATTERY TEST

SHORE POWER CHANGEOVER — COLD IRONING

SHORE POWER CONTROLS

SHORE SUPPLY STATUS

Shore Voltage— V

Shore Frequency— Hz

Shore AvailableNO

Phase Sequence—

Shore CBOPEN

SYNCHRONISING CHECK

Ship Bus Voltage440 V

Voltage Match—

Freq Match—

Ready to CloseNO

CHANGEOVER PROCEDURE

1. Confirm shore supply available
2. Check voltage and phase match
3. Close shore power breaker
4. Transfer load to shore
5. Open DG breakers in sequence
6. Stop generators (if cold ironing)

POWER SYSTEM TRENDS — REAL-TIME MONITORING

TREND CONTROLS

ACTIVE TRENDS

Bus A Voltage 440 V

Bus A Frequency 60.0 Hz

DG-1 Load 850 kW

DG-2 Load — kW

Total Load 850 kW

TREND WINDOW

ALARMS RECORDED

No events recorded.