Wiring question
 

Hi all, just trying to finish up my long list of upgrades this year on my boat and I was wondering what the opinion was on wiring size.

Boat is an 04 Supreme V220, has 2 batteries with perko, and used to have a 2 amp system that I'm changing to a 3 amp to run tower speakers (Entity 1010's)

The amps are:

Memphis Audio Power Reference 100.4(came with boat) 50A Fuse
Rockford Fosgate Punch 325.1 (came with boat) 40A Fuse
Precision Power A1200 (class ab old school monster, from my teenage days) Dual 60A Fuses

These are all located under the passenger seat next to the helm.

So It looks like total amperage is 50+40+120 = 210 Amps

Right now there's a dual 4 gauge feed for the power, from the batteries in the v drive side compartments, and a single 4 gauge ground going back.

I don't think that the wire will be big enough and was contemplating on the best way to upgrade. However, the boat budget is pretty tapped, as I did a heater, depth finder, and a lot of other upgrades in the off season, not to mention buying the boat. Didn't expect to get the tower speakers, but a price came up that I had to jump on.

Would it be worthwhile to swap the 4 AWG ground wire to a 1/0 wire? I'd then re-use the ground wire as another positive, thus giving me 3 x 4AWG's for power wire, and 1/0 for the ground.

Eventually I'll upgrade to a 1/0 positive wire as well, but I'm just trying to keep the price down for now.

Thoughts?

Thanks in advance!

it would cost more, but I'd run 1/0 power and ground. It would look cleaner, unless you hid everything real good.

I'm in 100% agreement with you and the 1/0 power and ground and that's where this will end up at. I'm not worried about looks, and will probably re-do everything this winter. Main focus this year is get the thing up and running and in the water!!

It's a circuit. You need to have as much wire on one side as on the other. So if you have 0 awg on your ground, no matter what you have on the power side, you're circuit would be limited to what you could pull through the 0 awg. If my calculations are correct, 0awg is only slightly more conductive than 2x 4 awg. You'd need to step up to 00 to match/beat 3x4awg.

Shawndoggy:

That makes sense. I'm thinking that the end wire size should be 1/0 gauge. So if I run a new ground, 1/0 gauge, I'll have an "extra" piece of 4 gauge laying around. Which is why I was thinking of just adding it into the power feed. Otherwise I'll just pull it out.

One thing I should add, if it makes any difference:

The memphis (boat amp) runs 6, 4 ohm speakers
The Rockford (sub amp) runs one 10" DVC speaker
The PPI amp will run the tower speakers at 4 ohm.

Thanks for any and all help.

Eric - the cabling is the back bone of your system. my advice is this

"WIRE IT RIGHT THE FIRST TIME". You'll thank yourself later...

1/0 gauge from the batteries to the distro block(s)
4 gauge from the block(s) to the amplifiers.

-Brian
Exile Audio