Car Fridge/Dual Battery

[Ryzz Advanced Member Find all posts View Profile Close Ryzz]

There is pic in my build up of where I mounted my fuse box. It's nice and neat plus it's easy to get to.

http://www.pradopoint.com/showthread...-s-2011-VX-D4D

VXWesty

Nice install in the wiring, my doesnt look anywhere near that nice, plus my plugs are on the door to the compartment where the fuse block is. I didnt think to drill into the sides to run the wires in, that makes it look very neat. Kudos!

[Lorenzo Senior Member Find all posts View Profile Close Lorenzo]

First of all, the ARB 47L fridge, without a doubt, is the best fridge of have ever owned. The current (amps) draw is nothing compared to the Engel's counterpart which I have owned as well. Its just the small things as well that add up like being able to remove the lid, that have mattered to me.
Second, when it comes to cable size Matt knows what he is talking about and he will probably agree with my line of thinking on dual battery set ups. There are two ways to go, one with an expensive charge unit, eg. Ctek 250 Dual and cheap batteries like the All Rounder and the Amp Tech (Supercharge) brands, both wet lead acid. Or a cheap isolator, eg. Redarc SBI12 and expensive batteries like the Optima Blue Tops which are an AGM battery.
Up to you really which way you go, but do your home work. If you are planning on travelling in remote areas, corrugated tracks, etc., it is probably a good idea to mount your service battery in the rear of the vehicle (120 series) because of the guard cracking problem. Incorporate it into your drawer set up and for the ARB fridge you need to mount a merit plug at the rear. I always install them on the left hand front of the rear so the fridge cable doesn't get stuck in the fridge sliders.
The Roo.

Roo,

I've been reading mixed info on the SBI12. Is it correct that this isolator doesn't like different batteries running through the circuits? (eg. std cranking battery and a deep cycle?) Other's have suggested the Piranha 140.

I'm thinking of getting an Exide ED5 as my aux. As I said it's not going to do a whole lot of work so don't want to get the best battery money can buy.

[Ryzz Advanced Member Find all posts View Profile Close Ryzz]

Roo,

I've been reading mixed info on the SBI12. Is it correct that this isolator doesn't like different batteries running through the circuits? (eg. std cranking battery and a deep cycle?) Other's have suggested the Piranha 140.

I'm thinking of getting an Exide ED5 as my aux. As I said it's not going to do a whole lot of work so don't want to get the best battery money can buy.

The Redarc doesnt care much about voltage types or battery types. The limitation is the alternator doesnt charge two different battery types perfectly, to charge it perfectly your better to go a dc-dc charger. The Redarc is just a selonoid that opens and closes the circuit between the two batteris at pretermined voltages, to make sure you dont flatten the cranking battery.

[AJ120 Out of control poster! Find all posts View Profile Close AJ120]

I don't claim to be any sort of expert on dual batteries or electrics; but in my opinion people tend to over complicate things around setting up dual batteries. Your alternator will charge whatever battery you put in, to run your second battery all you really need is some sort of switch to isolate it from the cranking battery so you don't flattten both batteries. I have the SBI12 and have had wet cell and AGM batteries and also charge a third battery in the CT with a direct hook up from the cranking battery to the trailer through an anderson plug, all simple straight forward stuff. If anything the SBI12 is overkill IMO as a $20 solenoid hooked up to the oil pressure switch will do the job just as well.

As I said I am no expert, when I researched this topic I asked a number of guys in my 4wd club what they run, they all use the SBI12, none of them are on forums, so they buy the first battery they find at the auto store, no one I spoke to had any issues whatsoever with their system.

I am yet to understand why miilions of cars are sold with just an alternator charging the battery and this works fine, yet as soon as we add a second battery people spend a fortune on these DC-DC chargers, it just doesn't make any sense to me at all.

I have just returned home from a 2 week trip running an ARB 47litre fridge and an autofridge as a freezer, as well as running lights, water pumps, inverter etc etc, no problems, same as the last two week trip earlier this year and 8 weeks last year.

Remember KISS (keep it simple sir)

Cheers Andrew

[Matty80 Avid PP Poster! Find all posts View Profile Close Matty80]

well said mate...

Its not exactly like having redundant, UPS backup supplies with auto change over mains and emergency setups to power redundant dynamic positioning computer systems.

Its just a car, simple, basic, extra low voltage installation.

EDIT: still have to get the cable sizes and protection correct though...

[Lorenzo Senior Member Find all posts View Profile Close Lorenzo]

Lozenzo, How did that trip go anyway?

Bad news mate, it got cancelled. One of my mates went on a surprise O/S trip, and another one got his PhD approved (he's becoming a marine biologist) and had to go away the same week to start it. So I canned it for now. Gives me more time to sort out the rig and make it an even better tourer.

Back on topic, I think I worked it out. Going to get the SBI12, and just a standard $200 battery, deep cycle or non, I'll work that out when I get to the battery shop. And yes Matt, I promise I'll use the correct cable and run the earth back to the -ve terminal of the battery

Loz

[Matty80 Avid PP Poster! Find all posts View Profile Close Matty80]

And yes Matt, I promise I'll use the correct cable and run the earth back to the -ve terminal of the battery

No worries mate! Any questions, let us know...

Pity about that trip though, have to get another one planned as soon as mate!

[Brains Find all posts View Profile Close Brains]

AJ120,

Firstly great to meet you at GTG, thanks for your welding demonstration on the Sunday, I only wish I lived closer so I could learn more from your skills.

I too agree with the KISS principle and like you said the easiest way to install a second battery is with some form of isolator. I too have been running a Redarc SBi12 in my personal vehicle and 5 work vehicles. It is a simple method to charge a second battery and from my research suited my use. I do believe that these DC to DC chargers are more suited to caravans and when long driving times will be experienced. From my experience I have not had any issues with my personal vehicle or any of our work vehicles running the SBi12's and these systems charge the battery suitably to run fridges and other equipment. Like any battery we still charge them overnight on a Ctek mains charger about once every 3-4 months.

[Lorenzo Senior Member Find all posts View Profile Close Lorenzo]

No worries mate! Any questions, let us know...

Pity about that trip though, have to get another one planned as soon as mate!

No probs. My car is still at the panel beaters, but the word on the street is that I'll get it back this friday! Can't wait it's been 8 weeks almost!

We're re-planning for maybe Feb-March next year... worse comes to worse I'll go by myself and maybe one of you guys can tag along as my support vehicles

[AJ120 Out of control poster! Find all posts View Profile Close AJ120]

AJ120,

Firstly great to meet you at GTG, thanks for your welding demonstration on the Sunday, I only wish I lived closer so I could learn more from your skills.

Yes also good to meet you, pity you couldn't have come for the whole week, it was fantastic. Glad you enjoyed the welding demo. look forward to catching up again down the track somewhere.

Cheers Andrew

[Lorenzo Senior Member Find all posts View Profile Close Lorenzo]

It's like I said, it's how the Ctek unit looks after your batteries that matters to me, so you can feel safe using the cheaper deep cycle batteries. If I was going to do an install with the SBI12, I would be recommending good quality batteries, eg. Optima as there is no boost on the current. As far as installing the Ctek 250 Dual, it is a piece of cake and is a simple system, easy as (kiss). Each to their own.
The Roo.

Roo,

as I said, this is a very basic install and it'll only be used part time. Fridge won't be in the car every day. It'll be in there maybe 6 days out of every month, so I don't want to get the best possible gear for such little use. If I was doing a 12 month trip and relied on it daily then yes, I'd follow your reasoning.

If further down the track my needs change, or I want to do a 12 month trip, then I'll upgrade everything. No plans for that in the forseeable future, and a very tight budget. I think that what I'm getting is more then enough for my needs. I could almost get away with just using the crank battery, but putting in the second for peace of mind.

Lorenzo

[Lorenzo Senior Member Find all posts View Profile Close Lorenzo]

Piranha Tray and SBI12 arrived in the post today $169 & $85 respectively (delivered).

Also, should be getting car back from panel beater Thursday/Friday. Going to buy cable + Battery this weekend.

So it's 8 B&S (8mm2) for the battery connections, what thickness should I run for the fridge? Going to buy a cable with 2 wires in it.
Also, what battery would be good to go with the SBI12 and the standard prado battery ex factory? Budget is $200.

[Madkore Avid PP Poster! Find all posts View Profile Close Madkore]

Always nice to drag up an old thread.

A fuse block is a nice way to keep things neat when it comes to the positive connections, but is there any way to tidy up the negative side of things rather than having them all hanging off the negative terminal of my aux battery?

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

Projecta sell these:

[Corigator Avid PP Poster! Find all posts View Profile Close Corigator]

I use one of these -http://www.narva.com.au/pressrelease...s-messy-wiring

It includes 12 earth terminals. I've mounted mine below the steering column on a bracket. I bought mine from battery world. I sent a 100 amp feed + and - through the firewall to it.

Very handy