Different current from house bank batteries

[DotDun]

Originally Posted by Cadence

I don't by the wiring. Paralleled batteries are electrically the same no matter where the taps are. As long as the wire ga. is sufficient connecting them.

Originally Posted by Emouchet

I totally agree in that too. Electrons motion follows simple rules.
I would make sure also there is no hidden resistor in the connection such as corrosion.

There will be millivolt differences between the batteries due to voltage drop if not wired as shown above. Over time, that will take a toll on the batteries due to unbalanced charging. The diagram above puts all batteries at the same wire distance (i.e. voltage drop) from the load/charging source.

[Cadence]

Originally Posted by guyrj33

I suggest cleaning ALL of the connections to the underperforming battery and testing again.

A good thought. I was making the assumption that anyone with a clamp on ammeter has done that?

[Cheechako]

-Clean connections.
-Charge batteries overnight, then feel them. if the center one is hot you may have a shorted cell.
-alternatively, remove the cables after charging from all batteries. Wait a while and measure voltage, a shorted cell will make that battery voltage low.

[guyrj33]

Originally Posted by Emouchet

I totally agree in that too. Electrons motion follows simple rules.
I would make sure also there is no hidden resistor in the connection such as corrosion.

This is only true in the classroom, in the real world the small differences do make a difference.

[Cadence]

Originally Posted by Cheechako

-Clean connections.
-Charge batteries overnight, then feel them. if the center one is hot you may have a shorted cell.
-alternatively, remove the cables after charging from all batteries. Wait a while and measure voltage, a shorted cell will make that battery voltage low.

I thought that took a load tester almost a dead short.

[ZULU40]

Originally Posted by Cadence

I don't by the wiring. Paralleled batteries are electrically the same no matter where the taps are. As long as the wire ga. is sufficient connecting them.

not tested the idea myself, but the views on this page are now commonplace. If your connections are as in the first illustration, change them

SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

[Cadence]

Originally Posted by ZULU40

not tested the idea myself, but the views on this page are now commonplace. If your connections are as in the first illustration, change them

SmartGauge Electronics - Interconnecting multiple batteries to form one larger bank

They are only physically different not electrically. I'd opt. for the minimum amount of expensive wire and if some one wants to nit pick resistance. If 2/0 isn't big enough run a bus bar.

[ZULU40]

Originally Posted by Cadence

They are only physically different not electrically. I'd opt. for the minimum amount of expensive wire and if some one wants to nit pick resistance. If 2/0 isn't big enough run a bus bar.

well, we are gonna disagree here
just to add I thought resistances was what it was all about
Im staying with the modern engineering convention
which IMO appears tested and true

however, theyre your batteries, you do what you wanna

cheers

[DotDun]

Originally Posted by Cadence

They are only physically different not electrically. I'd opt. for the minimum amount of expensive wire and if some one wants to nit pick resistance. If 2/0 isn't big enough run a bus bar.

They are electrically different.

[sailorboy1]

Personally assuming all the connections are good I seriously doubt any wire inbalance is causing a 300+% difference in current for such a tiny tiny load!!!!!!!! I would be much more inclined to believe a problem with the bank 2 battery

[Cadence]

Originally Posted by sailorboy1

Personally assuming all the connections are good I seriously doubt any wire inbalance is causing a 300+% difference in current for such a tiny tiny load!!!!!!!! I would be much more inclined to believe a problem with the bank 2 battery

I'd guess he has checked the connections for corrosion.

[DotDun]

Originally Posted by sailorboy1

Personally assuming all the connections are good I seriously doubt any wire inbalance is causing a 300+% difference in current for such a tiny tiny load!!!!!!!! I would be much more inclined to believe a problem with the bank 2 battery

No doubt. The immediate symptoms are not due to the wiring imbalance, it's a battery failure. But, the battery failure *could* have been caused over time by a wiring imbalance.

[Cadence]

Originally Posted by DotDun

No doubt. The immediate symptoms are not due to the wiring imbalance, it's a battery failure. But, the battery failure *could* have been caused over time by a wiring imbalance.

I doubt it. Cells sulfate from MFG possibly?

[Tikka]

lots of good suggestion , Assumption they all parallel and they all charged exactly the same is a problem. I would partly discharge the bank, than individually fully charge.
Repeat the test 1+2, 2+3, 123, than deside.

[rotorman]

Originally Posted by john61ct

I hope not literally the same point.

Do you mean to posts on the same battery?

Or are you wired as per the diagram just above?

I can not paste image here. No. I have 2 posts (+ and -) outside the batteries. To this post all batteries are connected with the same length with very heavy cables. All connections are in very good condition.
This configuration is different from the image you have pasted but I struggle to understand why the connection you suggested is better.