dual batteries?

[Frenchy]

For what you're doing isolated for sure, say you lived way up north and needed to crank it over for a while, parallel

[567234ta]

in your situation where you just need to do it occasionally, you could just put a fuse on the positive line and pull it when you are running the stereo. end of the day just put the fuse back in and go. with a dual setup you can run a long time though, especially with good batteries like optimas. I have a volt meter digital display i made that tells you the voltage, you could do something like that and when it got down low you could start it.

[lo-lyf]

I would use a cirquit breaker or marine battery selector switch before using a fuse in this application. Relays are automatic though, no popping the hood to turn a switch, or trip a breaker, etc. Great idea none-the-less for a cheap way to keep one isolated.

[567234ta]

I would use a cirquit breaker or marine battery selector switch before using a fuse in this application. Relays are automatic though, no popping the hood to turn a switch, or trip a breaker, etc. Great idea none-the-less for a cheap way to keep one isolated.

yeah i like the idea of a relay the best really. easy, cheap and a simple switch in the dash can control it. there are so many ways to go about it, you could have it setup where it's one battery, the other battery, or both. for the life of the batteries it's best to run them dual all the time and have matched batteries.

the peak voltage should be as close as possible to each other. i got 2 red top optimas that are still working after 12 years now.

[lo-lyf]

yeah i like the idea of a relay the best really. easy, cheap and a simple switch in the dash can control it. there are so many ways to go about it, you could have it setup where it's one battery, the other battery, or both. for the life of the batteries it's best to run them dual all the time and have matched batteries.

the peak voltage should be as close as possible to each other. i got 2 red top optimas that are still working after 12 years now.

.............or you could run it off of ignition and not have any switches. just use the ignition that stays on during crank(pink wire for GM).

[oleshifty]

I was going to run mine in parallel and just use one of the drag racing emergency shut off switches in the cable to shut it off when I knew i was going to be playing radio for really long time. That way when you turn the switch on, you're basically jumping your own car...but while driving/starting/etc you have benefit of 2 batteries.

[shakey]

I'm not a big fan of isolators and most alternator companies will agree with me. Draining a battery so far is very hard on the alternator to recharge because its built for maintaining, not charging. My duals are parallelled. Another option would be to parallel them then put in a voltage alarm that will kill power after alerting you that its to low. A lot of inverters will use those.