Fuses. Breakers etc for Dual Battery install

[nicbeer]

Hey all,

After some info.

Will be running 2 x N70 95ah batteries,

100amp Redarc with 50-75mm2 cabling running around the back of the engine bay.

80 series diesel.

Wondering do you have to install a fuse , breaker? and if so what have others installed?

[phippsy]

Was thinking about this as well as I'm putting in a dual battery soon. When I worked at a truck workshop, most of them had auto and manual circuit breakers which I think might be a good option. Pic of what I mean

[nicbeer]

Ditto,

i didnt have them in old zook but i had a manual switch in that.

i am new to solenoid setups.

if i am going with a breaker what amperage do i go for. bearing in mind i have got a diesel and from what i have read draw more amps then petrols..?

I am also running a large power feed to the back of 4b for fridge etc.
i am thinking not running fuse/breaker on the main lines but fit a 100A on the rear feed wire instead.

[TroopiePete]

Was thinking about this as well as I'm putting in a dual battery soon. When I worked at a truck workshop, most of them had auto and manual circuit breakers which I think might be a good option. Pic of what I mean

May seem like a nice idea and I have used these Circuit Breakers but they are quite fragile and not very waterproof.
But it did survive a trip out to the Simpson and back.

[Black Bull]

Run a good Isolator like the Redarc, you don't need breakers, just make sure you use fuse blocks off the batteries for you accessories.

Most important thing is use split convoluted tubing and secure your wiring, you won't have any trouble nor need mains breakers

[TroopiePete]

Run a good Isolator like the Redarc, you don't need breakers, just make sure you use fuse blocks off the batteries for you accessories.

Most important thing is use split convoluted tubing and secure your wiring, you won't have any trouble nor need mains breakers

Good advice, I have experienced the down side of not doing this during our trip to Dalhousie Springs on the rocky roads after many thousands of Km of corrugated roads then the Rocky road was enough to move the main battery towards the AC Compressor jamming the battery linking cables then rubbing then through to short out on the AC pipework - fortunately all it did was stop the motor and blow a fuse or two - did this a couple of times before I found the actual cause of the fault - but very very frighting when you are just about to cross the Simpson Desert.

[drivesafe]

Hi nicbeer, if all the batteries are in the engine bay then you don’t need anything.

If you want to put something in, then you need to put one at both ends of the cable joining the auxiliary batteries to the cranking battery and no matter how thick your cable is, you are highly unlikely to draw more than about 50 amps for long periods of time.

So two 50 amp auto resetting circuit breakers will give you the best protection with the minimal effect on the operation of your set up.

As to the cable running to the rear, unless you are planning on pulling some serious currents, a 30 amp auto resetting circuit breaker will give you all the protection you need.

[nicbeer]

Cheers Drivesafe,

Basically what i was thinking. i'll do the aux feed only then.

the rear cable will be a main feed to the back, fridge, rear camp / reverse lights, power sockets so will work out breaker size on cable size that goes in.

it will be at least 4b$s going in i think.

[melcor]

you dont say if your running a winch or not .... we do duel batt systems at work all the time ..we never run breakers or fuses anless reqested or if battery is in the rear.. redarc is good but make sure you have a manual overide switch drawing power from the second battery otherwise if the first batt goes flat there is no way to link up to the second batt and you'll then still need jumpers to start the vehicle.. make sure the cable is run in split loom or similar and that its secured firmly to avoid any chance of rub through or heat damage.. if you decide to run circuit breakers or fuses dont forget to allow for exrta start up currents for any motors(can be 30% higher then continuous current)

[Rodeo98]

Hi melcor
could you please post a diagram of what you do for the manual override switch? im about to oput in a dual battery setup with the second battery in the back of my ute and have been wondering how to wire it all up properly

[brissle]

what else are you going to be running besides the fridge?....lights?
if it were me i would run seperate wires for the fridge and lights so you can put a swicth at the front for the lights pretty handy i reckon.
6mm for the fridge and 6mm for the lights will be heaps enough and the you can just use 30amp fuses for protection

[nicbeer]

Hey Brissle,

no winch yet..

I will be running same as my old car, one main feed to rear fusebox distribution to

rear camp-lite / reverse light
fridge (5-7amp/h) autofridge
rear power outlets
interior camp light (LED quite possible)
ARB air compressor new style, (still debating on this, dont think i can space under bonnet for it.