wiring size?

[lloydy]

Hi,
I have a 10 amp battery charger that i will be fitting under the rear seat, a leisure battery (80amp) behind front seat and a starter battery in engine bay.
As a rule of thumb, what size cable will i need to connect it all up. Also, what size cable would i use for 12v power points, lighting, ect.
Any pointers would be great

[dansimpson]

Try this

http://www.solar-wind.co.uk/cable-sizing-DC-cables.html

I usually allow for 3% or 4% loss

Dan

[lloydy]

Ok, cheers. I suppose i'm working off 10 amps as thats what the charger produces?

[Red Westie]

That wire gauge calculator is unreal it is recommending 6mm2 cable over 4 meters with a 3% loss...thats 42amp cable to carry 10amps, RIDICULOUS!

I would say 2mm2 (17.5amp) or 3mm2 (27.5amp) to be over cautious for the battery charger.
3mm2for the power plugs, 2mm2 for the interior lights.

See the wire gauge against amp rating:

http://www.autoelectricsupplies.co.uk/product/66

Doubling on all your likely loads to choose the wire gauge should be fine and of course it doesn't hurt to go next size up again where that rule is border line.

Martin

[lloydy]

That wire gauge calculator is unreal it is recommending 6mm2 cable over 4 meters with a 3% loss...thats 42amp cable to carry 10amps, RIDICULOUS!

I would say 2mm2 (17.5amp) or 3mm2 (27.5amp) to be over cautious for the battery charger.
3mm2for the power plugs, 2mm2 for the interior lights.

See the wire gauge against amp rating:

http://www.autoelectricsupplies.co.uk/product/66

Doubling on all your likely loads to choose the wire gauge should be fine and of course it doesn't hurt to go next size up again where that rule is border line.

Martin

Thats great! Seems more realistic, and for a change some reasonable pricing. That seems my biggest problem at the moment (silly pricing) Should pop down to my local motor factors really
Thanks, Lloyd