Outer Limits 4x4 Board

Gday,

I've just had a dual battery installed - using the SMART system.

I was curious as to whether i can use my aux battery to somehow jumpstart my car should my main battery somehow run flat?

I realise it's hard to run your main flat with the SMART system but just want to know in case it was to somehow happen one day - more out of curiosity than anything.

Can anyone shed some light on whether this is possible and if so how to do it.

Cheers for any advice.

Not sure about the Smart system but with my Baintech dual battery you can simply bridge two of the points on the solenoid to join the batteries together.

Not sure on your setup , if you can't this is what I did , If you can , disregard , or In plain terms you need to earth both batteries to the block with a 8mm thick cable. Then use the same cable to run between the batteries and in betwwen you will need a solenoid to switch the power on and off. You will need to put a switch either in cab or engine bay to switch solenoid coil off and on. Do not use a winch solenoid , they are not suitable , you need an isolation solenoid. You will need to fuse the Isolation solenoid coil positive , Cheers Paul.

jumper leads

jav wrote:jumper leads

x2

hey gravel, is there a small blue wire with a clear cover coming off the solenoid?

TOY-08V wrote:hey gravel, is there a small blue wire with a clear cover coming off the solenoid?

Yeah mate there's a small blue wire with a clear plastic end on it - underneath the clear plastic it says "override".

??????????

sounds of it, im presuming its a redarc or a copy or similiar. You can wire a jumpstart button into that wire.

Look on the redarc website or on here for a link or something, its arround.

you can definitely find it on the redarc website, www.redarc.com.au

dean

edit: go to redarc.com.au,

products, L-Z, Smart Start and theres a whole bunch of pdf files that tell how to do what ever it is you want, wicnh off both, jumpstart, always star off both, run parallel etc.

dean

yeh i have a red arc isolator... you hook that up to a spring released push button which uses a relay inside the isolator to bypass the main battery and crank off the accessory battery..

It (on this isolator) does not link both batteries together but bypasses the main (otherwise if both are hooked togeter it will equalise the charge and you still may not start it)

I know it works because when i got the duel batteries set up in mine, i went to drive away from the auto electrics place and my cranking (main) battery was flat...
Press the button, hear a click (from the solenoid) and bang it starts...

Hope it helps.

Brad

As mine are earthed alike, and only the positive cables run through the solenoid, I keep one short, thick cable with alligator clips in the back.
You can then just join the two positive terminals together to jump start your car from the aux battery.

Cheers boys - big help - mine is a Redarc too so i'll have a look at that site and suss it out.

HotFourOk wrote:As mine are earthed alike, and only the positive cables run through the solenoid, I keep one short, thick cable with alligator clips in the back.
You can then just join the two positive terminals together to jump start your car from the aux battery.

thats how i would do it on mine if i ever needed to

HotFourOk wrote:As mine are earthed alike, and only the positive cables run through the solenoid, I keep one short, thick cable with alligator clips in the back.
You can then just join the two positive terminals together to jump start your car from the aux battery.

wouldnt/couldnt that just equlise the charge and possibly loose both?

barbz wrote:

HotFourOk wrote:As mine are earthed alike, and only the positive cables run through the solenoid, I keep one short, thick cable with alligator clips in the back.
You can then just join the two positive terminals together to jump start your car from the aux battery.

wouldnt/couldnt that just equlise the charge and possibly loose both?

Only if the dud battery has a short cell. To "recharge" a flat (but otherwise healthy) 12V lead acid battery requires a higher voltage than another 12V battery can generate during discharge.

jav wrote:jumper leads

x3 Besides they are handy should someone else need a jump start.

barbz wrote:

HotFourOk wrote:As mine are earthed alike, and only the positive cables run through the solenoid, I keep one short, thick cable with alligator clips in the back.
You can then just join the two positive terminals together to jump start your car from the aux battery.

wouldnt/couldnt that just equlise the charge and possibly loose both?

Not for such a short period of time no. It will only draw the currewnt needed for starting through the jumper lead, and once started, take the lead off.

If your solenoid has a bypass connector or similar, make sure that the unit can handle the large current draw required for starting.
I know a lot of lower grade units only have a rated current capacity of around 100-200A.

brad 93hilux wrote:yeh i have a red arc isolator... you hook that up to a spring released push button which uses a relay inside the isolator to bypass the main battery and crank off the accessory battery..

It (on this isolator) does not link both batteries together but bypasses the main (otherwise if both are hooked togeter it will equalise the charge and you still may not start it)

I know it works because when i got the duel batteries set up in mine, i went to drive away from the auto electrics place and my cranking (main) battery was flat...
Press the button, hear a click (from the solenoid) and bang it starts...

Hope it helps.

Brad

Bypassing the main battery sounds like the better idea to me. if the main batt has collapsed a cell or similar you are hooking into a dead short basically .. one that the solinoid may not be able to handle