Battery power
#1
Just curious but, if I were parked, engine off with the ICE playing (can't imagine why I'd be doing this, nothing to do with being in the back seat's or anything I'm sure ) but just supposing this scenario occured, how long would it be before I wouldn't have enough battery power left to start the car? Given 25w RMS per channel head unit 130w RMS amp with 12" sub and cd changer.
#4
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Most car batteries are roughly 50-70Ah. Which means about 720W for an hour. Divide 720 by current drain and there you have it. Look in amp/head unit manual for max current draw - or double output of amp (***. 50% eff). Or add up fuses - my headunit 10A (must take less!) and amp 40A max poss 50A - therefore I would get twitchy after 1 hour at reasonable volumes, but you might get 2 at low volume. I had a friend back in school days whose PUG 309 battery flattened in 15mins with his system on!
#5
...and if you're playing Barry White to sooth your lover then there'll be loads of subwoofer action just from his voice = loads of current draw.
If you're planning on doing this often then it's a good idea to get a second battery and a big momma of a relay to isolate it from your starting battery... Autoleads do a relay for about 20 quid.
If you're planning on doing this often then it's a good idea to get a second battery and a big momma of a relay to isolate it from your starting battery... Autoleads do a relay for about 20 quid.
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