Which Isolator for Dual Battery

Mate,
There are so many options available, but IMHO it depends on what sort of bloke you are (ssuming you ARE in fact a "bloke"....can't tell from your nickname??)
What I mean by that is......are you the type of bloke who tends to monitor things and like to take responsibility for switching things on/off etc.......or would you prefer a fully automated system that you put in and then just use it until one day it doesn't work and you have to scratch your freckle wondering "what's happened?"

I like the 1st option better and for that reason I use a simply manual isolator linked to a switch in the cab and also both batt's are linked to a voltmeter (I can switch it to monitor either batt, but when truck is running and isolator turned on to link the batt's together, the readout is the same whichever way the switch is facing). I also have a "fail-safe" in that the isolator cannot be ON unless the motor is running. This was simply achieved by running a wire from the windscreen wiper motor.....if the wipers won't work, the isolator is OFF.

It's sounds more difficult the way I explain it, but works well in practice and I can keep up to date with what power I have available in either/both my batt's anytime I like.

I have an inherent distrust in electronic things that can go phyyyysssssttt for no apparent reason; usually at the most inconvenient time possible.

Cheers,

Roachie

I've used a Sure Power Diode isolator for nearly 30 years with absolutely no problems, my troopy had the same one your 80 series would require, 120 amp with a voltage sensing terminal, wiring instructions in the box, You just need to buy the Toyota battery box for the opposite side to whichever your battery is currently on. The isolator is/was around the $230 mark and the battery box is around $100 from memory, cheaper from a wrecker.

Hi Chenj3,
I just been through this process!!! - I've been running a dual battery setup for 5 years using the $50 jaycar isolator without a prob.... well that was until easter weekend - when it decided it had had enough and wouldnt charge my 2nd battery. Apparently the mosfets in the jaycar kits have a habbit of just giving up when they've had enough - static senstivie tempramental little buggers it seems.

I agree with the others - I don't like electronics - much prefer something more basic/relaible - so was considering a basic solonoid setup. However - I liked the automatic setup that the jaycar isolator had - charged and isolated automaically basically didn't even need to think about it - it was great!

So after deep thought - I decided that the electronic pirahana kit ($290 isolator) was the best option - yes its electronic - BUT - it has a 5 year waranty and has been around a long time now - and its automatic - no need to worry my little head while I'm on holidays. So I have just taken the punt that they have all the bugs ironed out now and have gone with that.

The old Jacar one was great - but was a cheapo you have to assemble yourself - not much quality control or reassurance there at all - so I've now placed the crucial task of keeping my beer cold into the experienced hands of pirahna! Cold beer is now a certainty... well almost... ;)

-Myfourby

Hi Chenj3,

As others have said, the choice is wide. If cost is a consideration, a simple solenoid is an easy and inexpensive option. It's also fairly foolproof. Just connect the activating wire to someplace that only has power when the ignition is in the 'on' position. You can also wire it up so that you have to manually switch it on - avoiding the risk of a flat battery sucking power from the starter battery, although I've never experienced this as a problem.

If you're handy with a welder, a cradle is easily made from some 25mm angle iron. Get a hold-down bracket from Kmart and you're in business. I have used this setup in several vehicles and it's survived for many years in places such as Gibb River Road, etc. Have a look at some of the commercially available ones - there's not that much to them! A good coat of anti-rust primer, some decent paint and you'll never know the difference.

Hi Chen3,

There is a lot of merit in what is said above. However, if you just want to buy a kit and fit it, I would also go for the Piranha. I went for the ARB unit and fitted it myself. Very easy, but you pay a premium.
In retrospect I would have done the Piranha.

just another opinion.

good luck

Local workshop doesn't like electronics much either so they used a voltage sensitive relay in mine with nice large cables to jumper and use for a winch when I exentually get around to fit one. Just needs a minor charge and it connects to charge the second battery.

I have a simple solenoid here chenj3 if you want it. I paid about $75 for it and then went and bought the Redarc as it had spike protection and was automatic, my email is behind the pic below if you click on it, email me if you would like it.

I have recently purchased the ARB dual batt kit for $525 and installed myself, came with full instructions so even a dummy like myself had no prob's installing. $800 seems a bit steep, did the price include labour? I have a 80 series n/a diesel.

I use the Redarc isolator, competely automatic. Has the added advantage of a manual overide via a switch if you need to use the second battery to start from.

chenj3
Agree to go with REDARC, guys on website are a lot of help as well. Have spoken to a couple of auto sparkies who use all the time, never had a failure. Isolator $150, Battery $110, Battery Tray around $100, then all you need is the wiring to connect, so around $450 all up. (Quote from %$B, around $800). Rest of ready made system is profit. Purchase a redarc and ask them for wiring diagram and recommendations, free advice is very good.
Rolande

Thank All,
I think all your valuable comments have me more confidient what I need and whai should I do next. Thank you for your time and your experience again.

Have fun 4WDing!

chenj3,
When we bought our car 5 years ago it was fitted with an Auxillary battery charged by a simple solenoid which parralleled the main and auxillary batteries whenever the engine was running.
Normally this isn't much of a problem, provided your two batteries are of similar size and in good condition.
Then we were struck by the dreaded voltage spike.
This caused the UHF radio to forget itself. It wouldn't scan, had no duplex, no priority channel, etc. Luckily the EPROM didn't fry itself.
The radio was reprogrammed free of charge by the great people at GME, even though it was well out of warranty. Thanks again fellas!
I then decided to install a Redarc Relay.
It was chosen because it has spike suppression, it monitors the main battery before charging the auxillary, it is Aussie made, a switch enables the two batteries to be parrallelled for emergency starting if the main fails, it has a 2 year warranty.
The redarc cost $110 at Ashdowns in Adelaide.
They have branches in other states.
Motor Traders quoted $160.
Redarc recommend installing fuses or circuit breakers for protection.
Two maxi-fuse holders and 4 X 60 Amp fuses (2 spares) were $23, also from Ashdowns.
The local Auto Electrician charged $30 for 3 Metres of 8mm cable plus a handfull of solder type lugs and joiners.
10 Metres of convoluted tubing (that corrugated stuff with the split along it) was $3.
Some heatshrink insulation was $5 from Jaycar. The Auto Electrician probably has it , but I forgot to ask.
Total cost, $171.
It took a day or so to remove the old solenoid and its wiring and install the new one.
I haven't yet installed the remote switch for the parralleling function. One of these days.

Before the Forum experts begin attacking me about the 60 Amp fuse size, let me explain.
When the main battery is flat and the redarc is closed, using the pushbutton, to parrallel it with the auxillary, the idea is to wait a while before starting the vehicle. This enables the main to be partially charged, otherwise it could be damaged by excessive current draw.
Therefore, 60 Amp fuses are sufficient to control the current flow.
If you don't believe me, ring Redarc. They told me.

Redarc has a free technical assistance line on (08) 8186 5633.
Their informative website is www.redarc.com.au
I hope this is of some assistance.

Trev