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I own a vehicle. I plan to add a system, a high output alternator, and a second battery in the rear. My alternator will be sized so that it has enough output to maintain voltage at or above 13.4 Volts with the system at wide open throttle.

Q. How do I determine the correct gauge of cable between all of the components? [Power / ground cable . . . not speaker cable, etc.]

Go. Hint: A thorough explanation here will be required, and an example used to illustrate your explanation would be beneficial.

Tony Candela - SMD Sales & Marketing
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its not like you'll ever actually answer the question :D

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This isn't teeball. YOU DO NOT GET A TROPHY JUST BECAUSE YOU SHOW UP. Put the work in and then maybe get the respect when it has been earned

151.6 with single 12 at 41 hz

153.2 with 2 12's at 43 hz

power: dd m4

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I doubt you will like this answer but,

I think it is a bad idea to design a system to run at a certain voltage "full tilt", you can't calculate that unless you are just burping. Music is dynamic, and something as simple as the temperature outside can effect charging voltage.

So, yeah, thats my two cents.

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Thick enough gauge wire so the amps will see little to no voltage drop at full tilt, at full alternator output, assuming the alternator exceeds the total amperage of the system and have 0.01 resistance or less through all lengths of wire...

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1. First figure out the length of your power runs

2. Figure out the power draw for each run (value of fuse(s) for said device(s) as per the manufactures suggestion)

3. Do a bing/google search for "Wire Run Calculator 12v" http://www.powerstream.com/Wire_Size.htm or http://www.solar-wind.co.uk/cable-sizing-DC-cables.html Has an active tool

4. Figure for each device and use the proper fuse and cable.

5. For the main battery to battery connection add fuse values for all devices together and find the proper gauge using the tool from step 3.

6. For the run from front to back use a fuse (same value as #5) on both ends of positive power cable so you have a breakable link on both batteries.

6. Also do the "Big 3"

Edited by Skater229
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2010 Chevy  HHR Panel (Work in progress)

Pioneer AVHX-5800BHS

McLaren MLM880's and MLT2's 2ea per door on a DC 175.4

Two DC Audio M4 Level 5 15's On A DC5K

Alt CES 200/270+

4ea Banks of Maxwell 2.7v 3000f caps for a total of 2000f

1ea XS 3100 and 2ea NSB FT170 Batts for 450+ah 

Not a HUGE build but here it is... DC Audio HHR Build

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NEC Wire Ampacity chart is what I use. Assuming a copper conductor, of course.


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