GU Dual Battery System - Your comments on best brand of system

I have piranha system on mine, I run dual batteries, winch, fridge, 4 radios, 4 spotties, and have no hassles.

Also have a look at
http://www.rotronics.com.au/

Mail them, they will send you a CD with their catalog on it, then work out what you need there.

I've had an ARB system in my GU now for three years without a problem.

Chris,
My advice, for what it's worth...but it works for me is.....
Buy a suitable battery tray made to fit (say Pirahna/ARB etc)
I use a Exide N70ZZ cranking battery....got sick of dramas with Deep cycle jobbies.
I use a simple solenoid. This is wired so that it WILL NOT "join" the 2 batteries when the ignition is off (I took a wire off the wiper motor....if the wipers won't work, then the solenoid is "off"). However, as an added precaution and so that i can stay in control, I run that wire (ie the 1 from the wiper motor) through a switch next to the passenger's seat belt buckle. This means i can select if I do not want the 2nd battery hooked into the charging/starting system. Why? A couple of reasons....
1) If the truck has been sitting idle for a few days with accessories running off #2 batt, there is a chance it will have run down to a point whereby switching the ignition on may actually "equalise" the 2 batteries, making starting the motor difficult/impossible. I have a dashpod-mounted voltmeter which I can switch between the 2 batteries. I always check the charge of the #2 battery b4 starting and if it's low, I shut the switch off and only start on the #1 batt. I can then turn the switch and start charging #2 as soon as I reckon #1 has got enough charge in it.
2) If I always rely on both batteries to start the donk, then i will have no way of knowing if/when the #1 battery is on the way out. My truck is almost 4 years old and still has the original starting battery in it, but it is getting a bit sluggish and cranking the 4.2 on it's own.
I like to keep things simple (it matches my mind!!! LOL) and prefer to be in control of what is going on under the bonnet. All these computer controlled switching systems are okay for people who leave all their servicing up to mechanics and call the RAA/NRMA/RACV etc every time they've got a slight problem etc.
The way i see it, you only need a simple (but good quality) solenoid, a battery tray, some proper heavy cabling and soldered + crimped ends with heat shrink tubing, some cable ties and a switch + voltmeter (last 2 are optional).
Hope this makes sense.
Cya mate

Hi Chris,

I use a redarc solenoid on my GU. This system is the same as the ARB smart solenoid, but only 1/2 the cost for the solenoid (I paid $99 trade at coventrys vs $219 at ARB).

I have previously used Cole Hearsay switches and ordinary solenoids and this redarc solenoid is by far the easiest and most convenient.

redarc isolator

However, if you want the "best" isolator IMHO, its the Rotronics charge/isolator. It isolates each battery in turn and charges only that battery, that way you get the best charge rate from the alternator. However, due to its very high cost for the top of the range model (over $1,000 for 3 batt charger and in-cab monitor) I do not think its cost effective for most people.

Rotronics isolator selection page

Cheers

Captain

My advice for what its worth . Go and ask a few auto electricians what they think plus the forumites advice = good advice .

Chris,

Follow Roachies advice. His system is the most reliable and is exactly the way Auto Electricians set up their own cars. I couldn't even guess how many of those flash isolators I have repaired over the years or pulled out of vehicles to replace with the solenoid system

Chris, Follow Roachies advice. It is the best setup. As he says, use a starter battery and I have found it best if you use identical batteries. If you don't want to use switches which you may forget to turn off or on. You can put a push button type in the dash,(same as the push buttons that turn on the interior lights when you open your doors) which will disconnect the power to the solenoid as you start the vehicle. Once you start up, take your finger off the button and both batteries are charging. Also put in a low voltage cut out switch between your aux battery and your toys. cheers Tony

Ive fitted a few of these over the years using ARB trays and Seperators. Always fitted, always worked, Use N70zz(x) batts.

Bazzle ;)

My setup is very similar to Roachies. Except I join the positive terminals together and cut the negative of the starting battery. This way everything runs off the second battery (I use two cranking batteries) when the ignition is off.

I can also flick a switch to drop the relay so it is only charging the 2nd battery when driving so it charges quicker.

I only have a 2.6litre 4cyl Rodeo so doesn't take much to start it. I use two 30amp horn relays in parallel.

Total cost was $0 as I had all the bits in my garage. Except for the tray as that was $80 from ARB + $20 fitting.

I have had this system for 2 years and it hs not missed a beat.

Spiking the computer is said to be a risk with this setup however an auto sparky told me that so long as I put some charge into the 2nd battery after starting before dropping out the starting battery then all will be fine.

Utemad

ChrisM,
My opinion only!!!!!
I use a Redarc isolator with an ARB battery tray, had leads made by local electrical outlet from 300amp rated arc welding cables. N70ZZ Bond Calcium Starter Battery, switch in handy hole pre-drilled directly under steering column to join two batteries in case the worst happens, pirahna 7 block fuse board - total cost $380 installed myself and works by itself - no need for me to remember to change switches etc. Cost for complete ARB system - $563 without fuse block and in-cabin switch.
Rolande

2 x N70ZZL 17 plate cranking batteries 700cca $260
1 x Rotronics MH10 Isolator $250
Cables $20

Run all the accessories off the auxilliary battery except the winch which runs off the main battery.

No worries

Chris M
when you unpack the Redarc, read the instructions in bold on the specifications/instructions sheet, stating you must only use 2 x identical batteries.

Sory, the instructions state in bold:
"We recommended the use of similar style batteries in the one installation"

So I take it they don't recommend 'different' styles of batteries in the one installation, or they would not print the warning in bold?

The product Warranty sheet with the solenoid states:

"ON CONDITION THAT...
1. The product has been correctly installed in accordance with the product instructions on the reverse side of this sheet...........etc." does that mean if you don't use similar style batteries you will void the Warranty?

Chris,
I took this from the Exide web site, was the only 650 CCA battery listed, so I assume it is the battery sellected by your autoleck to work correctly with the Redarc solenoid?

PASSENGER BATTERIES
CODE- BATTERY- CCA- RC- L, W, H- Weight- Terminal
DIN88- Exide Advantage- 650- 140- 348,173,175- 19.6- RECESSED POST