Redarc Smar Start Dual Battery System

[lewi]

hey guys

just wondering how the redarc dbs system works with regards to the accessories.

I know that when the car is turned off, the redarc isolates the start battery when they batterys get down to 12.5 volts.

What I want to know is, if i take the keys out of the car, do the 12v sockets, stero, lights and stuff still all work all does the wiring need to be changed to hook them up the second battery,

Im just trying to find out if any extra wiring needs to be done to have things work with the keys out.

cheers

[bejay]

hi lewi i run 2 redarc in each of my cruisers all extra acc should be run from battery 2 all will fine hope this helps bejay

[Peter @ Aawen4x4]

You WILL need to do a fair bit of re-wiring to connect all the aux items to the aux battery, or everything will remain connected to the Start battery!

[physh]

can you make a redarc not automatically voltage controlled, but linked or unlinked only by a switch?

[steveandviv]

lewi, as Peter mentions you would need to re-wire those aux items that are already connected to the main battery. Depending on what you want the second battery for, IE, Fridge, lights etc you would be best to run a new loom for those items. If it's the radio etc that concerns you then it may pay to also connect it to the aux battery.

What I did was connect the fridge via a dedicated loom and then one another loom (indepentantly fused) and off that ran two additional out lets for any aux requirments.

[lewi]

What if i leave the keys in the car and turned to acc, will eveything then run off the second battery as the start battery is isolated?

[Peter @ Aawen4x4]

Usually when you fit these isolators it won't change anything to do with the normal electrical system unless YOU DO IT, or at least ask whoever fits it to do it! So as you would normally find everything connected to the main battery, and it will run off the main battery when the keys are in the car and set to acc, while the Aux battery will be isolated from them, and free to run ONLY those things that YOU have connected to it! You don't normally isolate the MAIN battery when those isolators separate them, you actually disconnect or isolate the Aux battery from the main battery, leaving the main connected to all the car std equipement; so that heavy use devices that get used for camping etc and are normally connected to the aux battery will not drain the battery you need to start the car, ie the main battery!

So if YOU haven't changed the wiring across to the main battery, DON'T RUN ANYTHING THAT TURNS ON OR OFF WITH THE CAR IGNITION CIRCUIT FOR LONG ONCE THE ENGINE IS STOPPED, IT WILL BE FLATTENING THE MAIN BATTERY!! The FRIDGE that you connected to the aux battery will be running off the aux battery and it will flatten it a lot quicker than any light or radio! If you want to run anything off the aux battery, you have to arrange for it to be transferred to run off the aux battery. Generally you would leave ALL the engine specific and car operation circuits and devices on the main battery, ie starter, headlights & parkers, driving lights, dash lights, std interior lights etc; while things like the car stereo, the UHF radio, additional internal fluro lights, the air compressor, your amp, etc would be run off the aux battery! One exception to that general rule would be an RFDS or HF Radio, that NEEDS to have pretty good battery power to work, and since the start battery is commonly the one that you save just so it will start your car, so that would be where you connect your HF! Unless of course you have a secondary charging system to keep either your aux battery up to scratch, or even just to keep a third battery on the bubble just to run the HF Radio.

So does that make sense lewi? If YOU haven't changed it, then all your std car fittings will STILL be running off your main (in other words the original) battery!

[lewi]

cheere peter, that was pretty much what i wanted to know. Just started my auto sparkie appreitnce ship (4 weeks ago) and wanted to know more about them. Should be able to sort out the wiring my self.

Chees again.

-lewi

[diehard]

I used to test my redarc was working by turning on the headlights....this would drain the main battery enough to trip the solenoid.

All the redarc does is allow the 2nd battery to be drained flat without affecting the main batteries charge. When you start the car, the solenoid reconnects the 2nd battery so it can be charged.

Like pete mentioned, any ADDITIONAL items (fridges, flouro lights etc) should be run off the 2nd battery, so if they do suck the charge out of it, you'll still be able to start the car off the main battery, and re-charge the 2nd.

[tommy222220_0]

Have just put a 2nd battery in the tray of my navara. Used a redarc solenoid as well.

My way of thinking was that if anything was accidently left on, ie headlights, stereo etc, then it would drain your main battery, leaving you stuck and no going anywhere fast. :(

So, I connected most of my accessories (headlights, stereo) to the second battery, leaving only the essential engine items connected to the main battery, ie ecu, starter etc. This can be done quite easily, although a little time consuming.

I used a couple of relays using both, an on and acc trigger wire. This is essentially the same as wiring an amp, (although the relay in an amp is mounted internally). This way there is no way of flattening your starting battery and everything operates the same as came from the factory.:waycool:

The only way you could get stuck, is if your starting battery fails (unlucky) but hopefully there may be still enough charge in your 2nd battery to start the car.

Also, the redarc can be manually overridden so the 2 battery are connected. see http://www.redarc.com.au/smartstart-techspec.pdf
Commonly used when winching, as it draws lots of current, ie more than you alternator can supply.

Hope this Helps u and good luck.

[sudso]

My set up is a little different. I've just got a solenoid only. As soon as the key is on Acc2 both batteries are linked together and get charged/discharged together.
I've got one stereo amp off the main battery and one off the aux but they dont get turned on unless triggered by the remote lead from the head unit, which only comes on in the Acc2. position anyway.
I've got other accessories that run of the aux battery (which is a wet cell Marine battery with deep cycling ability) including a winch and can run them from either just the aux, or from both batteries with the turn of a key.

I'm not sure yet though if the aux battery gets isolated when cranking the engine over but they both seem to discharge and charge evenly.
In the lock (ignition) position the only thing being powered is the clock and radio memory, and the security system which are all off the main battery.
I keep an eye on things and check both battery voltages at least once a week just in case there is too much difference in voltage between the batteries.

Also my ignition switch has two Accessory positions:
Acc1 & Acc2 but most auxillaries dont work unless its in the Acc2 position.

I'm in two minds about this set up, it has advantages and disadvantages. Not sure whether to leave it this way or not.

[502chev]

Usually when you fit these isolators it won't change anything to do with the normal electrical system unless YOU DO IT, or at least ask whoever fits it to do it! So as you would normally find everything connected to the main battery, and it will run off the main battery when the keys are in the car and set to acc, while the Aux battery will be isolated from them, and free to run ONLY those things that YOU have connected to it! You don't normally isolate the MAIN battery when those isolators separate them, you actually disconnect or isolate the Aux battery from the main battery, leaving the main connected to all the car std equipement; so that heavy use devices that get used for camping etc and are normally connected to the aux battery will not drain the battery you need to start the car, ie the main battery!

So if YOU haven't changed the wiring across to the main battery, DON'T RUN ANYTHING THAT TURNS ON OR OFF WITH THE CAR IGNITION CIRCUIT FOR LONG ONCE THE ENGINE IS STOPPED, IT WILL BE FLATTENING THE MAIN BATTERY!! The FRIDGE that you connected to the aux battery will be running off the aux battery and it will flatten it a lot quicker than any light or radio! If you want to run anything off the aux battery, you have to arrange for it to be transferred to run off the aux battery. Generally you would leave ALL the engine specific and car operation circuits and devices on the main battery, ie starter, headlights & parkers, driving lights, dash lights, std interior lights etc; while things like the car stereo, the UHF radio, additional internal fluro lights, the air compressor, your amp, etc would be run off the aux battery! One exception to that general rule would be an RFDS or HF Radio, that NEEDS to have pretty good battery power to work, and since the start battery is commonly the one that you save just so it will start your car, so that would be where you connect your HF! Unless of course you have a secondary charging system to keep either your aux battery up to scratch, or even just to keep a third battery on the bubble just to run the HF Radio.

So does that make sense lewi? If YOU haven't changed it, then all your std car fittings will STILL be running off your main (in other words the original) battery!

Second that.

[4x4xfar]

When I bought my GU Patrol a few years ago, the guy that owned it installed a 2nd battery, well, I took this thing out camping and if I didnt go with my mate I would have been screwed, Both batteries drained!

Turned out the wally had installed dual batteries alright, but had most of his accessories running off the start battery....wanker!

I bought a Redarc Solenoid and have since re-wired the whole thing, it's good now!

[matt_ratt]

wouldn't it just be eiser re wireing the stuff you need to run/start the engine?

i spose on an older car it would but maybe not a new one?

[mr_cougar79]

Im not a real lover of those cheap solenoids,yes they r simple to fit and run but in the case of a dead cell in just one of the 2 batteries the good battery suffers as a result of the most charge going to the dead cell and in the mean time the good batteries voltage decreases to the same voltage as the poor battery so this is why i hate that setup so much...LOL gee im a whinger hey!

[bungie]

With a redarc system you just run the fridge, camping lights, inverter, and any chargers etc off the second battery and leave everything else the way it was when manufactured.
If you flatten the starting battery you can do either, have the redarc wired up so as to just hold a button in the cab to connect both batteries to join and give you cranking power, or use jumper leads to connect the positive of both batteries together (if wired as per redarc your negatives are connected) and you can then use it to crank your car. Why rewire half the bloody vehicle when its not needed

[sudso]

I know that when the car is turned off, the redarc isolates the start battery when they batterys get down to 12.5 volts.
cheersIt only isolates the main battery from the auxillary when the voltage of the start battery alone drops below 12.7 volts. Everything thats connected on both batteries will still operate as normal.
It isolates the start battery from the aux so it doesnt get drained by the aux battery and the accessories connected to it. Then you've still got plenty of reserve power in your start battery to start the vehicle .

It will still supply charge to the aux battery even when the engine is off, but only while the start battery voltage is above 12.7 volts. Once it drops below that the Redarc isolates (disconnects) them from each other.
Bungie is right, you dont have to rewire half the vehicle but if you plan to run a lot of factory fitted accessories (not essential items) for a long time without the engine running then its a good idea to get them rewired to the aux battery.
Basic rule of thumb is: everything you need to use while driving the vehicle should be left wired as is by the factory (Added driving lights should be wired to the start battery too) but only things like the stereo or other non essentials can be rewired to the aux if desired to lessen the drain on the start battery when the engine isnt running.
Its essential that both batteries are in tip top condition in a dual battery system too. (remember the old saying: one rotten apple can ruin the whole bunch)
cheers

[100 TD]

Just a note on the voltages. You are both correct however.......
The older Redarc isolators used to connet at 13.6 volts and disconnect at 12.7 volts.
The newer ones connect at 13.2 volts and disconnect at 12.5v
Surepower isolators (ARB sell them) work at 13.2 and 12.8. This is my preference, however ARB want to much for them so Redarc gets my money.

[alex_cs]

the thing with the redarc is that as long as you dont flatten the second battery too much, if you have left your lights etc on, with the optional override button you can hold it in while turning the key and the redarc will start the car off the second battery, no need to manually jumpstart. has got me out of trouble several times.

[notowjoe]

Ive got a solinoid on mine,once the key is turned back to acc the second batterys is seperated from the start battery. But heres the twist every thing (frige,lights,etc) runs off the start battery and the second battery is left for starting if required. its a simple system and theres no rewireing. Once the key is turned to the start postion both batteries are linked in together for starting and charging once running.Yes i do agree if one battery drops a cell then you may get caught out but in saying that who would go away with out checking your batteries.