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Battery connections from solar charger

Damil 1776

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Jul 12, 2022
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Not sure if it matters, I searched and did not see a post about it. I have a 300ah lead acid battery bank, when running the cables from the charge controller, should I connect the + and - to the same battery or connect + to one battery and - to the farthest battery, or does it even matter? And also does it matter if my inverter connections are on the same battery post as the charge connection
 
It depends if you have a 12-24-36 or 48 volt battery bank. How many batteries? How are they wired?
 
They are old large clamp style 2000 watt power drive came out of my semi. I have the connections hooked to the same battery but not the one that are connected to the charge controler
 
Ok. Of course you have postive to positive and negative to negative on your batteries for them to be paralleled. Hook up your controller and inverter to the same connections. Positive on one side of your battery bank and negative on the opposite side of your battery bank. Lest say batteries are 1,2,3. Connect positive on battery number1 and negative on number 3. Make sense? That way your current flows through your battery bank and not just one of them your batteries should stay appx the same level that way. Make sure that all of your batteries have been charged fully before you hook them up.
 
Ok. Of course you have postive to positive and negative to negative on your batteries for them to be paralleled. Hook up your controller and inverter to the same connections. Positive on one side of your battery bank and negative on the opposite side of your battery bank. Lest say batteries are 1,2,3. Connect positive on battery number1 and negative on number 3. Make sense? That way your current flows through your battery bank and not just one of them your batteries should stay appx the same level that way. Make sure that all of your batteries have been charged fully before you hook them up.
Makes sense, thank you
 
I connect my Battery cables to #1 POS and #12 NEG
I connect my inverter cables to #1 NEG and #12 POS
It seems to work fine
 
12 batteries in parallel
That’s why I connect to #1 and #12
However I am switching to 48 volt using 4 batteries in series and connecting the 3 packs in parallel using the same type of connection
 
You should wire them more balanced imho- the batteries in the middle won’t see the charging and loads equally with the ends.
I have 8 lead batteries and what I did was run two sets of four with equal length cables parallel to terminal studs; that runs inside and feeds the inverter. Each set of four is cabled to be balanced parallel.
There’s a paper in the stickies iirc that shows that.
Some say that’s pickyuni but I could measure a difference so it can’t hurt and probably helps
 
Ok. Of course you have postive to positive and negative to negative on your batteries for them to be paralleled. Hook up your controller and inverter to the same connections. Positive on one side of your battery bank and negative on the opposite side of your battery bank. Lest say batteries are 1,2,3. Connect positive on battery number1 and negative on number 3. Make sense? That way your current flows through your battery bank and not just one of them your batteries should stay appx the same level that way. Make sure that all of your batteries have been charged fully before you hook them up.
My helper asks:

I wonder if that is still relevant when each battery has its own bms built inside it.
Seems like each battery turning itself on and off would be a much bigger factor than the zero ohm resistance of the jumper bars between the batteries.

In any case there is no harm in connecting to the opposite end. On an ohm meter its exactly the same.

I wonder how someone ever proved it was better (i.e.: having pos and neg connected at opposite ends).
 
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