Battery Isolator

Guy brought me this to hook two batteries together. He bought it used, and has no instructions. What exactly does it do?

i think it is used for running two batteries for separate purposes. if you have one battery for a stereo or compressor and one battery turning the starter, it would allow you to run one battery without drawing drain on the other.

So basically it lets the alternator charge them both at the same time without actually connecting them as one battery?

Edited: 12/12/2007 8:49:05 PM by lowromigo

Edited: 12/12/2007 8:31:35 PM by lowromigo

Edited: 12/12/2007 8:29:49 PM by lowromigo

Summit Racing has those exact ones, Powermaster, there $132.95 each, $146.00 something with tax and shipping. My buddy and I just ordered 1 each together. Here is the link to them http://store.summitracing.com/partdetail.asp?autofilter=1&part=PWM%2D904&N=700+115&autoview=sku With out the isolator the two batteries don't charge properly. Its just a better and safer way to run two batteries, were using it for stereo, so one battery runs the vehicle and the other is for stereo equipment. We bought 200 amp alternators, and that is a 200 amp isolator. So I'm running 1/0 cable from the alternator to the isolator then 4 gauge to the batteries from the isolator then from the battery to the amp. But my buddy is running 1/0 from his alternator to the isolator, then 4 gauge to his regular battery, 1/0 to his 2nd battery, then 1/0 to his fuse where it runs in 1/0 then out to two 4 gauges. Then the 4 gauges will go to one amp each. Since he has two amps and I have one.

right, that is how i understand it. the alternator charges both batteries, but it separates them so that they do not draw on each other. the battery that is wired to your stereo or other accessories can be run completely dead, but the isolator keeps the second battery from being drained by the first.

Yeah thats how I understand it to work also. Plus the second battery we are using is a different type, better suited for car audio.

Originally posted by TwistedMinis



So basically it lets the alternator charge them both at the same time without actually connecting them as one battery?

Yep that's it so you can run one dead but still be able to start your car.