questions about batteries and wiring

[doug118 0]

First off I just discovered this site and it's great! I've read through 10 pages in this section alone for some answers and got some good ones but some were unanswered so I'm going to through a bunch of questions out there and hopefully some of you can help me out

heres a quick rundown of what my plans are

15" btl

sundown saz3000

2x sundown 125.2

big 3

150 or 280 amp alt (will explain)

ok so I am unsure on the battery situation. I want to keep my voltage as close to 14v as possible for extended periods of time. I drive around the country so 8-10 hour trips aren't unusual. the largest alt I could find without breaking the bank is 150amps BUT someone told me they had a custom 280amp alt built in his stock casing so I'm waiting to see if he can get the same done for me

1) I plan to upgrade the front battery and am curious as to if something along the lines of a single powermaster d3100 or would running 2 d2400 be necessary?

2) wiring: how many "runs" would be sufficient? and that has confused me.. would you run say all 3 + wires to the + on 1 of the rear batteries and then link that battery to the 3rd with just 1 1/0? are there any pictures or diagrams showing how this is done properly?

3) could I get away with running 1 large fuse for each run close to the front battery and thats it? I plan on running a 200amp relay just from reading things in other posts about them and figured why not?

I know I'm forgetting a few question but will just add them as I remember

thanks in advance!

[shizzzon 461]

you don't need to upgrade your front battery, just add a single D3100 to the rear, get that 280A alt or the highest possible. Check out DC power alts, they have good pricing.

Get dual 200A relays in parallel if getting an alt larger than 220A amp to separate the front and rear batt.

When doing big 3, use largest possible wire, 1/0 preferred.

When running from front to rear battery, for cheap, run 2 runs of knukonceptz colossus 1/0 or 2 runs of 3/0 ultraflex at weldingsupply.com .

[Duran 387]

I would recommend 2 d3100's, that should be enough. As for the alternators, find out at what RPM's do they do rated power. And with the wire, run something between 2 aught and 4 aught wire, fuse with a 300 amp fuse at the front battery, and one more at your first battery in the rear, then just a jumper from battery 1 to battery 2, and ground your batteries both to the frame as you will with your front battery in the big 3.

[doug118 0]

I would recommend 2 d3100's, that should be enough. As for the alternators, find out at what RPM's do they do rated power. And with the wire, run something between 2 aught and 4 aught wire, fuse with a 300 amp fuse at the front battery, and one more at your first battery in the rear, then just a jumper from battery 1 to battery 2, and ground your batteries both to the frame as you will with your front battery in the big 3.

2 3100's wouldn't be overkill for just 1 3000 watt amp? not to mention thats a ton of weight and money. I forgot to mention this is going into a honda civic so I would like to keep the weight down as much as possible. I would be really happy if I could get away with just 1 3100

the 280 amp alt I mentioned earlier was built for $250 so I'm really hoping to get that. if not I will probably just fork over close to double that for one from DC.

on weldingsupply.com they only show the ultraflex available in 2/0 but I'd imagine thats plenty big enough. how does that stuff compare to the knuconceptz Kolossus Fleks? the welding cable 2/0 is only $7 more for a 50ft roll

and say for 2 runs, I would run both off the front battery, both get a fuse, and both get a relay. do they both NEED another fuse at the back battery? also should I run the ground from the front to the rear in the same fashion as the positive?

again, thanks for the help guys!

[shizzzon 461]

only front to rear for the power run.

There should be a fuse right after starting battery, right before back battery and right before amp.

[Duran 387]

You could get more from your car with 2 12's, I went that route. I have two 70 lb. batteries in my spare tire well. Powering my SAZ-3000D

You don't need 2 runs, just one. You should make it as large as possible...4/0. The welding wire is the same as the "car audio" wire. I have welding wire myself.

[doug118 0]

I plan to run my setup very similar to this one

does that short wire to the amp still need to be fused?

and my original plan was to do 2 12's but the largest I could make the box is 4.5 cubes and that would be pushing it so I figured 1 15 would be better in the small space since 2 12's would require 3.5-6 cubes.

oh and my spare tire well is filled with air ride stuff.

I would like to have it like that picture as far as batteries and large amp go, then air tank on the left side of the box and the mid/high amps in back of the box

[Duran 387]

There are 12's that would love that airspace, mine are in 4 cubes a piece. I only have one 12 in at the moment, and people guess I have two 15's.

[doug118 0]

duran I sent you a message

[Duran 387]

duran I sent you a message

Replied.

[doug118 0]

what kind of fuse holders do you guys use for wire over 1/0?

[Duran 387]

ANL fuse holders.

[doug118 0]

will these work?

http://www.vteworld.com/content/electromech/fuse/html/anl/anlfuse.php

if not, any links would be cool

[Duran 387]

Yes those will work, don't order fuses till you figure out which alternator you'll be using.

[doug118 0]

all I can do at this point is laugh

the black lines are power wire, orange is ground, and the fuses are these http://www.vteworld.com/content/electromech/fuse/html/anl/anb753.php

now will that work or did I fudge up on something?

also, should I run all 3 amps off of the 2nd battery or run the 2 mid/highs amps off of 1 battery and the 3000 off of another?

Edited August 16, 2009 by doug118

[doug118 0]

no one likes my cool drawing?

[SPLScion 3]

looks good to me, I only saw one problem. Both battery grounds in the back need to be grounded to the same point to avoid a ground loop. The best bet, tho not absolutely need is to run another 1/0 gauge wire from your grounds back to the front battery's neg. terminal. Of course to reduce cost you can just ground batteries in back just fine.

[doug118 0]

ok cool. I'm going to buy like 75ft of 2/0 so running the negatives from front to back wouldnt be a problem.

also those fuses look okay to use? and what about the amps question, should I run all 3 off of 1 battery?

[Duran 387]

looks good to me, I only saw one problem. Both battery grounds in the back need to be grounded to the same point to avoid a ground loop. The best bet, tho not absolutely need is to run another 1/0 gauge wire from your grounds back to the front battery's neg. terminal. Of course to reduce cost you can just ground batteries in back just fine.

Of he grounds correctly he won't have a ground loop. Both of my batteries are on their own ground on different parts of the frame. And you don't need to run a ground from front to back. When you do your front battery ground in 2/0, and ground your back batteries to the frame in 2/0 your essentially using your frame rail as your wire run.

You can connect all your amps to one battery if you wish, it doesn't matter, they are all connected anyways and you are really just making one BIG battery.