Battery Bank Wiring. Is this Correct?

[Hoohaa]

Hi. I am just looking for confirmation or a simple diagram that can set me straight.
I am adding a 4th battery to my house bank.
I am trying to post this on my phone while sitting on my cabin sole.
Thanks.


Sent from my GT-I9505 using Cruisers Sailing Forum mobile app

[Ex-Calif]

It is preferable to connect the "E" at the opposite end of the bank. This ensures equal loading of the battery bank.

i.e. Pos and Neg should be diagonally opposite from each other.

[Hoohaa]

This is what I think I have currently.
Does it look correct

Sent from my GT-I9505 using Cruisers Sailing Forum mobile app

[Ex-Calif]

This is only the house bank, right? Is there a separate start battery?

E = Engine block, right?

Is there any other ground bus? i.e. where do all the service circuits connect their ground?

I would definitely not be running 2 large gauge wires to the engine block.

If the batteries were number 1-4 from the bottom of your picture I would connect positive of #1 to the #1 pole of the battery switch and negative of #4 to the engine block. I would also have a heavy gauge negative form #4 going to a negative buss bar for all the service loads.

If you have a battery 5 (start batt) I would not have a problem with it's negative wired to #4 and the positive to the #2 position of the battery switch.

(edit - I think the attached is what you should be aiming for.)

[Hoohaa]

The earth is to an earth bus and yes I have a separate cranking battery. I am just going over the system and the second sketch is what I have. Minus the 4th battery at the top of the sketch.
I want to add that 4th battery on the top of the sketch.
Hope that clarifys it a bit better.

Sent from my GT-I9505 using Cruisers Sailing Forum mobile app

[Hoohaa]

E equals earth.

Sent from my GT-I9505 using Cruisers Sailing Forum mobile app

[Ex-Calif]

I know the need to build cables is a PITA but my sketch is still what you oughta shoot for, I think.

Note of course the positive bus also comes of the battery switch "C" post.

[Hoohaa]

Is this what you mean?


Sent from my GT-I9505 using Cruisers Sailing Forum mobile app

[Ex-Calif]

Yup!

[Hoohaa]

Thanks Ex. it's now clear in my head, what needs to be done here. Getting things clear in my head is no easy task. So your help is invaluable. Thanks.
One last thing. As I may not be able to get back to Witworths tomorrow. Will sketch number 2 still work for the short term?
Jeff.

Sent from my GT-I9505 using Cruisers Sailing Forum mobile app

[Ex-Calif]

Electrically sketch 2 works. The last sketch electrically even loads the bank. Better long term.

[JK n Smitty]

The sketch in post #8 is the correct way to go. Assuming these are all 12 volt batteries and you are going for a 12 volt system.

But adding a battery to an existing bank is s a bad idea. You will not get the full useful life out of the new battery. Essentially it get's artificially aged by the existing batteries. Batteries in a single bank should be purchased and put into use at the same time and you should check the date codes when you purchase them to ensure they are all the same age.

[DeepFrz]

Battery Maintenance | Trojan Battery Company
A link to a site with some excellent resources.

[Stumble]

Posting this link to these questions has almost become reflexive since it spells it out so much better than I can. SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

As you can see, what you have drawn is reasonable, but not ideal. At least if possible it is always better to make sure the batteries are as perfectly balanced as you can get them.

[Ex-Calif]

I think smartgauge is misleading on method 3 - I can't imagine a world where I want to gang 5 battery terminals together - A robust negative bus would be better. I think what SG is trying to point out is equal length wire runs.