Electrical System 12v and 240v

(From the Ops Notes 2012)

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Electrical System – 12 volt:

The main 12-volt round isolation switch is located behind the companionway steps. Current convention is to use No1.1 and 1.2 batteries for domestic use and No2 battery for engine starting.

A subsidiary smaller battery switch just starboard of the main switch allows selection between 1.1 and 1.2.

Do not run the engine with either battery switch in the off position as alternator damage may result.    

 

No1.1 and 1.2 batteries are  approx 100AH and were purchased in Apr 2010. (Both replaced in 2017)

No 1.1 battery is hard wired via a fusebox, forward of the batteries, to run VHF, Stereo Radio, Gas Alarm & Navtext. There is also a direct supply to both bilge pumps.

No2 battery approx. 100AH was purchased Apr 2011. Then 2018

 

Electric appliances and instruments on the 12-volt system are generally protected by a series of circuit breakers /push button switches (identified with symbols) on the rear saloon bulkhead for, from top to bottom:

• Engine instrument and all cockpit instrument. 

• Domestic water pump, earth return is attached to –ve post behind new chart table instrumentation.

• Cabin lights.  Note that there is some interconnection behind new chart table instrumentation.

• Bilge pump. Starboard. Beware the other supply to the pumps via the float switch.  This switch has been deliberately left unearthed, to avoid difficulties with the dual supply.

• Bilge pump. Port.

• Autohelm supply. 

 

Inside the cockpit locker is a fuse box supplying power to the Cockpit locker light.

 

The following numbers refer to the new engine instrument wiring diagram.

(details are in large folder under chart table )

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1. The Solenoid supply is via a relay behind the bulkhead between saloon and cockpit. The solenoid takes 27 amps for the few seconds of starting. Supply to the relay is via 2x1.5mm wires directly from the selector switch.

2. Supply to new engine instruments is via a 15 amp contact breaker (top switch of new switch panel on saloon/cockpit bulkhead) 

3. New earth return in new position near and behind new switch panel on saloon/cockpit bulkhead.

4. Fresh water temperature alarm is disconnected. It is via new circuitry (to get temperature alarm and display from a single sensor), but alarmed at too low a temperature.(about 60F)

5. Battery charging alarm.

6. Preheater supply is disconnected.

7. Oil pressure alarm, also via new circuitry (to get pressure alarm and display from a single sensor). This does work.

8. Raw water alarm, not fitted

9. Rev counter supply, reads about 20% less than before (due to new alternator pulley?)

10. Not fitted

11. Not fitted

12. Not fitted

13. Pressure gauge supply, pressure reads 4bar (50psi)

14. Temperature gauge supply, temperature reads 90C at 2000rpm

 

Refer to the page about batteries and chargers in this section of the website for more information

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Electrical System – Mains 240 volts:              

A mains shore power socket is located under the transom bridge on the starboard side, with a circuit breaker in the cockpit locker. The 220/ 240 volt supply can be wired differently at different marinas and vary between hook up points within the same marina.

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Polarity Tester: There is a Plug-in tester for checking polarity and earth. This is stored in 'the office', if it not in one of the three pin sockets near the chart table.

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