Huge Dilema...Alternator/bat combo

runteldat
10+ year member

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Ok - pushing 3000 watts help me with these two options.

#1 250amp alternator - 150/idle // powermaster d3100 in rear

#2 200 amp alternator - 200/idle // powermaster d3100 in rear. // with MLA module

I'm not sure which one to go with. I'm not the type to play my music all the time.

Maybe for 15min TOPS...I'll definitely be driving with the amps off most of the time.

With that said, how fast would that d3100 drain if I'm playing for 15min at idle?

....and how fast would they charge?

There's not enough battery 'tech' on this forum...just people recommending certain batteries etc.

Help appreciated.

Oh fyi - I'd only be doing 3000w if I could maintain 14 or so volts.

 
Do you have the option for a second 31 in the back?

With two 31's and the 250 amp you should be fine bossman, just be aware of the voltage as always with anything.

With one in the rear you'll still be fine. I dont suggest running it with the vehicle off, however.

And the 31 will get drained by 3k rms relatively quickly if you're not re-charging it at a decent rate.

With one you'll be able to play full songs without worrying much, just extensive periods of time you need to watch out. With two - crank it on up.

 
Do you have the option for a second 31 in the back?
With two 31's and the 300 amp you should be fine bossman, just be aware of the voltage as always with anything.

With one in the rear you'll still be fine. I dont suggest running it with the vehicle off, however.

And the 31 will get drained by 3k rms relatively quickly if you're not re-charging it at a decent rate.

With one you'll be able to play full songs without worrying much, just extensive periods of time you need to watch out. With two - crank it on up.
Yeah thats why I was thinking the 200amp/idle alternator - i'm assuming it'll charge fairly quickly - especially with a mla module. Um, sure I can do a second back there, once I budget that in. Things are expensive.

 
Oh yeah - what actually charges the batteries?

like, is it the amp rating that matters, or the voltage? Or a combination of both?

I think voltage plays a big part - like the voltage needs to be higher than the battery voltage to charge....but if I have a 200/amp idle alternator...is it pushing the "remaining" amps to the battery?

 
audiolife is a battery guru.
Since you dont plan to play long or even hardly at all.

i say option #1

save money
Yeah - I probably won't actually buy a MLA - for 180 its a rip off.

I'll probably just solder a 6A diode in the yellow wire. It should increase charging voltage by .6 or .7

 
yea when i am crusing down the highway i harldy ever have my old setup full blast and if so my stock alt on 1500rms kept it at 13.5 full tilt lights on and AC on and crusing doing 60mph

 
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