Question about running a Dual Battery System...

[killahbean 10+ year member]

before HO Alt Upgrade - Isolator

After HO Alt Upgrade - NO Isolator

Cause without isolator your two batteries aint fully charged with the stock alt anyways.....blahhhh

 

[knukonceptz 10+ year member]

That makes no sense, there seems to be a HUGE misconception around here as to what is a fully charged battery and I'll bet 2/3's dont even own a voltmeter to make this accessment.

Any time you add a second battery you should charge them with a battery charger first so you know your starting point. Check voltage of the batteries 30 minutes after you finish charging with a battery charger, write that number down. Drive your car for a week or two, wait 30 minutes after you shut off your car, check voltage again. You'll see how little loss you really have with a stock ALT under normal music listening conditions. A Larger ALT is a good thing, for some reason folks think the second battery is a terrible strain for any electrical system, its more of a cushion then anything.........and an isolator is a waste for the majority of audio folks

 

[qtipextra 5,000+ posts]

So if you have a huge system, with 550 amps of max current draw(with (2) 275 amp HO Alts), as well as 2 of these Stinger batteries, and you plan to hardly ever playing your system without your car running (so your car is always running when your thumpin), do you need a relay/isolator?

 

[knukonceptz 10+ year member]

So if you have a huge system, with 550 amps of max current draw(with (2) 275 amp HO Alts), as well as 2 of these Stinger batteries, and you plan to hardly ever playing your system without your car running (so your car is always running when your thumpin), do you need a relay/isolator?
Notice: 500 amps from alt, 550 total max draw, hence the 2nd battery.

Nope, no point in having it

 

[qtipextra 5,000+ posts]

Didnt think so. So basically unless you want back up power, an isolator is just absolutley usless?

 

[knukonceptz 10+ year member]

If you want the ability to have the rear battery just for the stereo so you can jam with the car off - an isolator is for you. If you would rather have double the reserve capacity for the entire electrical system - an isolator is not for you.

With the second option you can jam twice as long with the car off though too

 

[qtipextra 5,000+ posts]

Yea, thanks.

And I just noticed, 2 275 amp alts is 550 amps, not 500, 1 bat would prob be okay anyway.