Electrical Help....

[swanson37]

Howdy All and greetings from a damp Australia (that's right after about 5 years of drought we have flooding ) )

My boat has three batteries (2 house and one engine).
The engine battery is connected to the engine and that's it, nothing else. It has it's own switch to turn on when I want to start the engine.

The house batteries are connected up to the usual 1-2-both switch. I want to be able to charge the house batteries from the alternator and bought a blue sea 60 amp ACR. The text talks about 'battery banks' which I assume means I'm allowed to have batteries in parallel in seperate banks and the diagrams show battery 1 and battery 2 with a common ground connection.

So, in order for the ACR to work it looks like I need to connect the engine battery into the common earth (to complete the circuit I suppose). So I guess my question is, can I parallel my house batteries and connect them to position 2 of my
selector switch and then connect my engine battery positive up to position 1 of the switch and the engine battery negative to the ground whilst leaving the existing engine wiring in place? (Hopefully some of you will still be awake at the end of that description ) )

I know this sort of thing is not so easy if you can't actually see it, I am not posting a picture of my wiring and batteries because the previous owner should have been shot for crimes commited to wiring.

One more question, (I'll post a picture if this gets no response)
I have this gizmo in my battery compartment, it looks a little like a heat sink, it has what looks rather like a small spark plug through the middle and at the back has a wire that goes to the common connection on my 1-2-both switch. At the front it has a long wire that goes nowhere (not entirely suprising, today I found 17 wires which served absolutely no pupose whatsoever, I mean both ends not connected, or near, a blessed thing). I suppose the wire could have gone somewhere originally, so I am asking if I can take the thing out ????

Answers on an electronic postcard please

p.s. Sorry for the length of the post...

 

[Niander]

post a pic ...is it an excess power dump commonly used with wind genys

 

[Pye_End]

[ QUOTE ]


So, in order for the ACR to work it looks like I need to connect the engine battery into the common earth (to complete the circuit I suppose). So I guess my question is, can I parallel my house batteries and connect them to position 2 of my
selector switch and then connect my engine battery positive up to position 1 of the switch and the engine battery negative to the ground whilst leaving the existing engine wiring in place? (Hopefully some of you will still be awake at the end of that description ) )

[/ QUOTE ]

Yes, although some will argue the merits of a split diode system.


[ QUOTE ]

One more question, (I'll post a picture if this gets no response)
I have this gizmo in my battery compartment, it looks a little like a heat sink, it has what looks rather like a small spark plug through the middle and at the back has a wire that goes to the common connection on my 1-2-both switch. At the front it has a long wire that goes nowhere (not entirely suprising, today I found 17 wires which served absolutely no pupose whatsoever, I mean both ends not connected, or near, a blessed thing). I suppose the wire could have gone somewhere originally, so I am asking if I can take the thing out ????


[/ QUOTE ]

No idea!

 

[hightech]

Greetings from an equally flooded UK.

Unusual switch arrangement, normaly the off-1-2-both switch would have the engine battery and the domestics connected, that way the both position will allow engine starting on all batteries and conversely will allow the alternator to charge both batteries too. Quite why there would be a need to have a switch to seperate the domestic banks is a mystery, generally both batteris would be paralled permanently to provide on big battery.

Anyway, in the configuration you have, the ACR would connect from the engine battery to the domestic batteries with the neg to the common for all batteries. then when the engine battery got charged enough the ACR would cut in and connect the domestics to the alternator too.

The finned thingy is likely to be a diode versin of the ACR.

 

[swanson37]

Thanks for the responses, I know the situation with the 1-2-both switch is odd, but I did say that the previous owner should have been shot, his other crimes included varnishing a teak deck, hand painting the cockpit and coachroof so that it looks like a turner seascape (in one colour) and pretty much being a useless pratt when it came to anything involving boat maintenance. According to other reports he was somewhat of a dubious sailor as well.
I'll post a pic of the odd thing to save the guess work (maybe)

Cheers all and have good weekend

 

[jollyjacktar]

On solution is to have seperate on/off main switches for each battery with a common earth return. Thus enabling any combinations of the three to be used or be charging at any time.

Another is to use the 1-2 switch with say 1 for the engine battery and 2 for the house battery. If two house batteries then another on/off can be used in parallel coming off the 2 terminal for the second battery. This is a total manual system.

For automatic switching and protection then you need to use splitting diodes and charge/isolator relays etc which are readily available nowdays. Best you talk to your local marine electrical operator. All easy to fit [bolt ons] and only require the proper cables made up for the job.

Have a chat with your local auto electrician or marine electrician to get a betteer undeerstanding of how these systems work and how to manage them while afloat.