Battery bank connections

Hi there,

Starting to look into putting a new battery bank into our boat and found this tutorial on how best to make the connections from SmartGauge Electronics;

SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

Watchya think?

I use method #2.

I use both depending on how long the cables are, but I prefer #2 if possible.

Interesting??

When I bought my boat the four batteries, divided in two banks, were wired like example #1. My brother looked at it and immediately moved the ground cables so they were wired like #2. He said that was the proper way to wire mulple batteries in parallel. I never knew why exactly, but makes sense.

Thanks for the post, that's good information.

Once again the Trawler Forum gives me a big AH HA. I just wired in eight new house bank batteries and did it like #1 example. I will be changing it to #2.

That's been posted here before in previous battery discussions, but it's good information. I have that page bookmarked in my boat electrical links.

When I recabled, I used Method #2.

I think that this topic is like asking how many angels can dance on the head of a pin.

The whole rational for these schemes is to make sure that each battery receives exactly the same voltage as the others. But does anyone really think that there is a significant voltage drop between batteries?

50 amps through 2/0 cable 3' long (about the round trip distance between three batteries with even the worst wiring configuration- #1) is about a hundredth of a volt.

I use a variant of #2, in that my DC, non-inverter load is taken from one end and my inverter load is taken from the other end.

Don't know if this is good or bad but it seems to make sense to me.

When charging the bank is split in two with each half charged separately.

Marty

djmarchand said:

I think that this topic is like asking how many angels can dance on the head of a pin.

The whole rational for these schemes is to make sure that each battery receives exactly the same voltage as the others. But does anyone really think that there is a significant voltage drop between batteries?

50 amps through 2/0 cable 3' long (about the round trip distance between three batteries with even the worst wiring configuration- #1) is about a hundredth of a volt.

Click to expand...

I tend to agree that there are other factors that may be a bigger issue than just the way you line up the cables...but if all else is perfect...why not.....

I also. Agree. what seems good and theory does not always work out in actual practice

Thanks for the general vote of confidence in this source of information. It's all pretty much voodoo mystical mumbo-jumbo to me!

Here's a series of articles from the same site, written for people who's brains aren't wired for wiring things, so to speak;

SmartGauge Electronics - Technical Section - page 1

For folks that get batteries with an auto style post , that are very hard to connect , remember NAPA sells a terminal they book as military style that will allow std eye terminals to be used , and ganged if required

.P or N as required.Cheaper by the box.

http://www.expeditionportal.com/forum/threads/22091-Best-Place-to-buy-Military-Battery-Terminals

Is what they look like , and full covers are available as required .

Also there harder to find bur copper bolts and washers , not SS or brass, will loose less juice in all connections.Esp the big ones like the Ground that may need to pass lots of amps at different times .

Hey, I got that one right! Maybe that's why my Xantrex charger works so well while others find them to be junk. Not to start that debate once again ...

<The whole rational for these schemes is to make sure that each battery receives exactly the same voltage as the others. But does anyone really think that there is a significant voltage drop between batteries?>

Who would care?

A batt charged at 14.15V will last as long and charge as well as one that receives 14.20V, so where is the problem?

To live long and prosper batts need to NOT be killed.

Low water , discharge deep, and let the batt sit for weeks , or over charging will kill batts faster than a 5 ft difference in their charge lead.