Power Distribution System

General Location

Power Distribution

The Main Switchboard is the hub of the electrical distribution system. Everything ties into the 480 Volt Bus in the Main Switchboard.Some devices and sub-panels are directly connected to the bus through breakers. Other sub-panels are connected to the main bus through step-down transformers that divide the power to 220 volt systems or 120 volt systems.Keep in mind, the main bus is divided into a port and starboard side; linked by the bus tie breaker (normally closed). Shore power and the Port Generator feed the starboard side of the bus, and the Starboard Generator feeds the port side of the bus. Also, off-ship power comes of the port side of the bus.

Yeah, it’s a little backwards, but that’s what we got. Take a look at the next slide for clarification…

Main Switchboard

Power Distribution

Starboard Genset (#2)Port Genset (#1)

Off-Ship Power 50 amp breaker

Shore Power In 100 amp breaker

Buss Tie BreakerNormally Closed

Power DistributionBreakers off the Main Bus (Starboard side of bus)

Deck Crane HPU

120 Volt Transformer T-3

220 Volt Transformer T-1

460 Volt FiFi Panel #1

Spares

Port Motor Controller (MCC) Breaker (Connects Port Motor control panel to port side of 480 volt bus.)

Power DistributionBreakers off the Main Bus (Port side of bus)

Spare

Fwd Capstan HPUAft Capstan HPU

Spare

Off Ship Power (Export)

460 Volt FiFi Panel #2

120 Volt Transformer T-4

220 Volt Transformer T-2

Starboard Motor Controller (MCC) Breaker (Connects Starboard Motor control panel to starboard side of 460 volt bus.)

Power DistributionE/R 480 Volt Panels #1 and #2

MCC P401P and P403S

Items controlled from these panels:• Fire/GS/Ballast pump• Auxiliary Sea Water

Cooling pumps (VSP and gearbox cooling)

• Tempered Water Cooling pumps (for A/C system)

• F.O. Transfer Pumps• Black Water Transfer

Pumps• Grey Water Transfer

Pumps• Bilge Pump• Rescue Platform HPU

Power DistributionE/R 480 Volt Panels #1 and #2

MCC P401P and P403S

Open this panel up, and you will find the breakers for:• Breathing Air Compressor• Service Air Compressor #1• E/R Supply Fan #1• E/R Supply Fan #2• Service Air Compressor #2• HVAC/CBRN Electric Duct

Pre-Heater• VSP # 1 Main Control Power• VSP #2 Main Control Power• HVAC/CBRN Supply Fan #1• HVAC/CBRN Supply Fan #2

Power DistributionFiFi Panel #1

P402P 460 VoltCenterline of Aft Hold

Breakers for:• Foam Pumps 1 and 2• FiFi System Cabinet B• FiFi System Cabinet H• Port Main Engine Jacket

Water Heater• FiFi System Cabinet D• FiFi System Cabinet I• Stbd Main Engine Jacket

Water Heater• VSP Room Fan• Aft Hold Fan

Power DistributionFiFi Panel #2

P404S 460 VoltIn front of you as you enter Aft Hold

Breakers for:• Foam Pumps 3 and 4• FiFi System Cabint G• Pump Engine #1 Jacket

Water Heater• Reverse Cycle Heat Pump

Unit #2• Pump Engine #2 Jacket

Water Heater• Reverse Cycle Heat Pump

Unit #1• Electric Duct Heater (Make

up air handler)

Power DistributionStep Down Transformers

Power is stepped down form 480 Volt A/C from the main bus to 220 and 120 Volt A/C via transformers.

There are two (2) transformers for the 220 Volt A/C system and two for the 120 Volt A/C system. The system is configured this way for redundancy.

Should the primary transformer for either system fail, the transformer may be switched to the secondary at the incoming breaker boxes seen here.

120 Volt transformer switching on the top. 220 Volt transformer switching on the bottom.

Step Down Transformers

Power Distribution

Close-up of 220 Volt Transformer Incoming Breaker Box.

Ground Fault Detection

Mechanical Switch Plate

Power DistributionStep Down Transformers

120 Volt Transformers• #4• #3

220 Volt Transformers• #2• #1

Power Distribution220 Volt Panels

P200S and P200PAft Hold, Fwd Bulkhead, near Centerline

P200P P200S

Power Distribution220 Volt Panels

P200S and P200PAft Hold, Fwd Bulkhead, near Centerline

P200S Contains Breakers for:• Wheelhouse Fan Coil Unit #2• Cook Top (Galley)• Sea Chest Impressed Current System• Potable Water Pump #2• Water Heater• 55 Amp Machinery Room Welder

Receptacle #1• 55 Amp Machinery Room Welder

Receptacle #2• Deck Light Circuit #2• Wheelhouse Split System FCU #2

Power Distribution220 Volt Panels

P200S and P200PAft Hold, Fwd Bulkhead, near Centerline

P200P Contains Breakers For:• Wheelhouse Split System FCU#1• Potable Water Pump #1• Wheelhouse Fan Coil Unit #1• Pump #3/Engine #7 Jacket Water Heater

(C-12)• 55 Amp Equipment Room Welder

Receptacle• Deck Light Circuit #1• Wheelhouse Split System Condensing Unit

#2• Wheelhouse Demisting Fans• Intercom/P.A. System

Power Distribution110 Volt Panels

P100Aft E/R, Starboard SideP100 Contains Breakers for:

• 120 Volt Boat Deck Panel P101 and Whistle

• 120 Volt Hold Deck Panel P103• 24 Volt Emergency Batt. Charger#1• 120 Volt Main Deck Panel P102• 120 Volt Main Deck Panel P104• Navigation Lighting Main Supply• Central Machinery Alarm &

Monitoring Main Supply• CCTV System• General Alarm System Main Supply• Fire Alarm and Detection Main

Supply• 12 Volt Emergency Services Batt.

Charger #1

Power Distribution110 Volt Panels

P103 (Sub-Panel)Aft E/R, Port Side By Main Switch Board

P103 Contains Breakers For:• Main Deck Lighting Circuit #2• 24 Volt E/R Service Battery Charger #1• 24 Volt E/R Service Battery Charger #2• Hold Accommodation Lighting Circuit #2• Hold Accommodation Lighting Circuit #1• Machinery Space Receptacles Circuit #1• VSP #1 Auxiliary Power• VSP #2 Auxiliary Power• Machinery Space Lighting Circuit #1• FiFi System Cabinet C 110 VAC 32A for remote valves• FiFi System Cabinet E 110 VAC 10A for remote valves• FiFi System Cabinet F 110 VAC 32 A for remote valves• Machinery Receptacles Circuit #2• Machinery Receptacles Circuit #3• 24V Fire Monitor Battery Charger #2• Generator #2 Anti-Condensation Heater• Generator #2 Jacket Water Heater• U.V. Sterilizer• 24V Fire Monitor Battery Charger #1• Generator #1 Anti-Condensation Heater• Generator #1 Jacket Water Heater• Equipment Room Cord Reel (30A)

Power Distribution110 Volt Panels

P102 (Sub-Panel)Main Deck, Multipurpose Room

Starboard Side Aft

P102 Contains Breakers for:• Equipment Room Door• Boat Deck and Wheelhouse lighting Circuit #2• Refrigerator• Microwave• Coffee Maker• Hold Accommodation Lighting Circuit #1• Boat Deck and Main Deck Receptacle Circuit #1• Machinery Space Lighting Circuit #2• Boat Deck and Main Deck Receptacle Circuit #2• Pantry Receptacles Circuit• Main Deck Receptacles Circuit #1• Main Deck Receptacles Circuit #2• CIC Receptacles Circuit• Hold Accommodation Receptacles Circuit #2• Boat Deck WC Fan and Damper• CBRN Fan #2 Damper• Main Deck Lighting Circuit #1• ROV Outlet on Workbench (38 Amp)• CBRN Detection Fan• Main Deck Shower and WC Fan & Damper

Power Distribution110 Volt Panels

P104 (Sub-Panel)Boatdeck, HVAC Space Behind CIC

Starboard Side Aft

P104 Contains Breakers for:• Equipment Room Fan• CIC Fan Coil Unit #2• Multi-Purpose Room Fan Coil Unit #2• Recovery Area Fan Coil Unit• Galley Range Hood Damper System (Via Alarm System• CIC Fan Coil Unit #1• Multi-Purpose Room Fan Coil Unit #1• General Stores Fan Coil Unit• EMS Area Fan Coil Unit• Interior Fire Dampers

Power Distribution110 Volt Panels

P101 (Sub-Panel)Wheelhouse – Port Stack Bulkhead

P101 Contains Breakers for:• 24V Emergency Battery Charger #2• 12V Wheelhouse Service Battery Charger #1• 12V Wheelhouse Service Battery Charger #2• 12V Emergency Service Battery Charger #2• Window Wipers• Mast Floodlight• Law Enforcement Light #1• Law Enforcement Light #2• Boat Deck and Wheelhouse Lighting Circuit #1• Boat Deck and Wheelhouse Receptacles Circuit #1• Boat Deck and Wheelhouse Receptacles Circuit #2• Wheelhouse Top Receptacle• Wheelhouse Top Rail FWD & STBD Floodlights• Crane Basket Floodlights Circuit• Search Light #1• Searchlight #2• Ice Maker (Galley)• Portable Radio Chargers (Wheelhouse, CIC, Multipurpose Room)• Wheelhouse Top Rail AFT & Port Floodlights• CIC Communications Computer• Boat Deck Floodlights Circuit• Crane Basket Receptacles• Satellite Telephone/Internet• CBRN Fan #1 Damper