Rewiring a small cruiser

Slig

I have started the rewiring process (really needed doing) and I have a few questions. At the minute there are 2 batteries (leisure batteries 100 amp & 75 amp). battery one goes to the outboard engine and battery 2 does the domestics.

While this is a grand system it means that there is no charge coming into the domestic battery from the engine and no earth for the domestic power(I assume the engine is earthed). I plan on putting a battery selector switch in which should solve the first problem but will this earth the batteries? Aside from that, a few basics:

1. The switch panel (nav lights, cabin etc.). Is this better wired to the negaitive from the battery switch. I presume then there is some sort of bar that connects everything positive back to one outlet to go back to the battery switch. There isnt at the minute but there is everything from kettle leads to exposed copper wire connecting everything(or not in some cases) so I'm not surprised.

2. When I put in the battery selector switch, can I still run the electrics(12v) when both batteries are selected (24V?) will the extra voltage not mess everything up?

3. I am replacing the hodge-podge of wiring going from the battery terminals to the battery switch with new wiring, should I look for cable rated for 100-150 amp or just go for the biggest ones available?

4. How many fire extinguishers is too many? (considering the novice approach to the wiring )

Tabnabs

If you don't get an answer on here, you will be flooded with answers if you ask here

noby

This is a job I started myself, as there appeared to be several additions to the wiring over the years, and I wanted to tidy it up, and get everything working.
I'm no expet, so I'm hesitating on answering your questions directly, but a bit of searching around the web will get a lot of info. I know I've a lot of links saved at home.

A negative bar will tidy up a lot of the wiring to the switch panel; not sure if there is an advantage to wiring from negative though.
You wil be connecting your batteries to the battery switch in parallel, so when 'Both' is selected the voltage will be the same, but your power doubled, so no issue there.

My main aim is to tidy up what is there already. It's like a rat's nest behind the switch panel at the moment. My boat also came with a solar panel, which tops up the batteries, as my engine's alternator is knackered. I'm not sure what kind of boating you do, but will your engine be running long enough to keep the batteries charged?

Slig

noby wrote: »

This is a job I started myself, as there appeared to be several additions to the wiring over the years, and I wanted to tidy it up, and get everything working.
I'm no expet, so I'm hesitating on answering your questions directly, but a bit of searching around the web will get a lot of info. I know I've a lot of links saved at home.

A negative bar will tidy up a lot of the wiring to the switch panel; not sure if there is an advantage to wiring from negative though.
You wil be connecting your batteries to the battery switch in parallel, so when 'Both' is selected the voltage will be the same, but your power doubled, so no issue there.

My main aim is to tidy up what is there already. It's like a rat's nest behind the switch panel at the moment. My boat also came with a solar panel, which tops up the batteries, as my engine's alternator is knackered. I'm not sure what kind of boating you do, but will your engine be running long enough to keep the batteries charged?

I have been doing my bit of research and come up with this as option 1 which is a battery switch. The disadvantages are that the batteries could overheat and instead of topping up both batteries it will bring them to the same level

wilson10

If you're still in trouble, I found this very usefull.

http://shop.ebay.co.uk/items/_W0QQ_nkwZ12Q20voltQ20bibleQQ_armrsZ1QQ_fromZR40QQ_mdoZ