How much current do car batteries like an optima yellow top provide?

[mrjoeyjiffy 10+ year member]

I was talking to my friend about getting that RD amp that is on sale right now that claims 3000w at 1 ohm( my setup is 1.5 ohm so im guessing more like 2200w) now as I understand it you divide the watts by voltage to get current?

so at idle/engine off 2200/12 = 183 amps?

engine running = 152.7 amps?

I was told that my batteries would only supply as much current as my alternator provides(190 amps in my case) is this true?

if so would an isolator that isolated my stereo from drawing from my engine battery keep things ok?

any insight would be greatly appreciated.

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[audiolife 5,000+ posts]

I was talking to my friend about getting that RD amp that is on sale right now that claims 3000w at 1 ohm( my setup is 1.5 ohm so im guessing more like 2200w) now as I understand it you divide the watts by voltage to get current?
so at idle/engine off 2200/12 = 183 amps?

engine running = 152.7 amps?

I was told that my batteries would only supply as much current as my alternator provides(190 amps in my case) is this true?

if so would an isolator that isolated my stereo from drawing from my engine battery keep things ok?

any insight would be greatly appreciated.

How much current does it take to start a car? Can a battery power a sound system with the key off?

 

[mrjoeyjiffy 10+ year member]

I'm sorry I dont understand //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

 

[fuggles 10+ year member]

You've got it right sort of. Battery can supply more current than the alternator in short bursts. An example is starting the car. But on average the alternator needs to replenish the charge.

If your stereo draws more current (on average) than your alternator can supply, then your battery gets drained.

Kent