How to add new wiring circuit to my car for my PC? FAQ / tips / tricks needed.

**Arathranar** · 10-13-2004, 09:57 PM

I have a 2000 Subaru Impreza Outback Sport. I've decided I'm going to try a tank solution (to avoid the crank drop-out) hooked to the switched 12v (to avoid the voltage spike).

I need to add a new circuit - probably 15A, maybe 20A to support my PC's 200W dc-dc cpu via the 7.2Ah tank battery.

How do I go about doing this? What gauge wire do I need to do? How should I do in-line connections and the like? Are there any hints and tips you can give me? I haven't seen anything much along those lines in my trawling of this forum.

Thanks.

**edikp** · 10-14-2004, 02:19 PM

Check this out for wire gauge: http://www.the12volt.com/info/recwirsz.asp .

**archimense** · 10-14-2004, 03:06 PM

Buy a car amp wiring kit.

There are tons on eBay.

**wizawuza** · 10-14-2004, 03:37 PM

www.knukonceptz.com

high quality, low price.

**Arathranar** · 10-14-2004, 03:59 PM

Thanks - didn't even know amp installation kits existed. They might well be the best approach. I'll look into them.

**Arathranar** · 10-17-2004, 02:14 PM

Originally Posted by edikp

Check this out for wire gauge: http://www.the12volt.com/info/recwirsz.asp .

Hmm. This suggests (for 200W power - i.e. ~16A at 12V) that I use 10ga up to 4 feet, 8ga up to 12' and 4ga up 20'. Yet the amplifier pack I looked at in Schucks has 20' of 10ga wire to power the 200W amplifier.

It seems that web site is suggesting massive overkill. 8ga is enormously thick. 10ga isn't small.

**Arathranar** · 10-17-2004, 02:18 PM

And this, from the same page, is very questionable:
Current Draw by Power

Total RMS Power (watts) - Current Amps
100 - 16
200 - 32

Those just look plain wrong - 12V x 16A = 192W. It says RMS power - so is it talking about AC power signals? In which case, the whole page is probably misleading.

**edikp** · 10-18-2004, 12:26 AM

No, it's not misleading. Sorry for the confusion. The page I gave you is for wire gauge calculation for power amplifier. Amplifiers have efficiency figures, they used an amplifier that had a 50% efficiency hence the 50% tax.

I thought I could give you some kind of an idea for the wire gauge. Anyway, just disregard it.