Added 2 batteries - look ok?

[Allen_C]

I added one 12v deep cycle 105ah battery (B) to the tray in my new Alante 31v immediately but really want to have three or four. So, I added one more using the storage bay adjacent to the battery bay. Due to trying to keep the wires as short as possible, when I added "C" I used 9" 4 awg wires, the same gauge as originals. When I added "A", I had to use 35" 4 awg cables and ended up with the connections you see here.

Although I do not have the solar installed yet, the wires on the far left on "A" are what I plan. I know it is not optimal, but due to space and keeping cabling as short as possible I will use 12" of 6 awg (the max that will fit in the charge controller terminals).

Any issues with how this is all wired, other than not being optimal?

[Mustang65]

Question: Are ALL 3 batteries the same mfr. Model. Ah rating and close in age? If not, you can not hook them all together.

Since 3 batteries is an odd number of batteries (as in not an even number of batteries like 2, 4, 6...) for any special wiring, the best way to keep all the loads and charging currents as equal as possible is a simple "EQUAL" length of cable from each terminal of the batteries, to a terminating lug. One terminal lug for POSITIVE and one for NEGATIVE. You have an equal amount or cable resistance between each battery. The trick is keeping all cables equal in length.

Here are 4 different ways of hooking up 3 batteries in parallel. I "Xed" out the one that should not be used. Opps, have a duplicate included.

Good Luck,

Don

My Registry

RVing with SOLAR

[Allen_C]

Don, I understand the ideal/optimal way. In fact, I think you provided that info previously! Is there any issue with how I have it and is it better if I ran 36" cables between each battery (even though that is 27" longer than I need)?

[Mustang65]

What is the distance between battery "A" and battery "B"?
What is the distance between battery "B" and Battery "C"?

You do not have a balanced circuit between batteries which can have an affect on the charging of each battery.

Don

[Allen_C]

Originally Posted by Mustang65

What is the distance between battery "A" and battery "B"?
What is the distance between battery "B" and Battery "C"?

You do not have a balanced circuit between batteries which can have an affect on the charging of each battery.

Don

I should have included the physical distance initally...
about 29" between A and B with a storage bin wall in between.
B and C are next to each other in the battery tray. I really wish Jayco didn't spread everything around and weld the battery tray in place. With better planning four batteries could fit in the original compartment.

Basically, is it better to have longer cables and have it well balanced OR keep cables as short as possible and connect the way I currently have them?

Thanks!