Battery Balancer Image

Battery Balancer

Battery Balancer With Negative Ground


I have a battery array with 4x 12V AGM battery for an output of 24V that was discharging and charging not equally so we got ourself a battery balancer module. Problem is that the negative of the array is connected to the ground for lightning and safety purpose since the system is powering DC Pumps.

I cannot see in the manual if the balancer module can be used with grouned negative. If it is, what would be the ideal wiring.

Thanks !

moverm asked
moverm answered ·

2 Answers

Battery Balance too many batteries?


I have 48 x 12v AGM 135aH batteries and have them configured in 2s 24p. (3 x banks of 8 2s 8p).

The batteries are about 3 years old (used in a ups system)(All wired in series).

The 3 banks are connected together with 25mm x 6m Bars bars with positive feed on one end and negative on the other.

When I set them up they we fully charge and with 0.05 of volt of each other. I have 4 85/250 mppt charging these with a Mutiplus 5000Va /24 running ESS.

i have 3 x victron battey balancers 1 on each bank. They where in alarm state

I have disconnected and metered the batteries today and the batteries are at least 1.2v out.I am planning to get them all back up to fully charged using external charger

Am i expecting to much to have this amount of batteries in series parallel. They have been working great over the summer but maybe the have been getting slowly out of balance.

The only thing that has changed is I have started using a scheduled charge overnite from the the last 3 weeks.

Any thoughts would be greatly received.

Many Thanks

richie-gorrod asked
JohnC answered ·

3 Answers

Battery balancer wire gauge

Hi all,

I'm upgrading my battery bank to 2S4P 24v system using SBS 190F Batteries.

Ive just bough a battery balancer and will install it once the batteries arrive.

Will one unit be enough to balance the 4 strings?

What wire gauge should I use for it, +/- and mid?

Thank you

gabriele-rossi asked
kevgermany commented ·

4 Answers

Balancing 8x6v (48v) system with two balancers

first time poster looking for help with battery balancing

I am working on an electric boat conversion using 8 golf cart batteries (flooded lead acid 6v) wired in series. I purchased two of the HA02 balancers ( which each can balance 4 batteries of up to 12v each. i have wired the first to batteries 1-4 and the second to batteries 5-8. This is working well but it does still allow imbalances to occur between the first 4 and last 4 batteries in series.

I have seen people mention that it might be possible to balance all 8 batteries but it would require a 3rd HA02. I am not sure exactly how the wiring would look on this. Can anyone help me out?

second - I was thinking through how it might be possible to balance across the entire bank without adding a third balancer. I was curious if it might be possible to sort of parallel the Two balancers to monitor all batteries. My thought was to wire each input to overlapping pairs of batteries (therefore giving each 12v). This would be wired as:

balancer 1: 1/2, 3/4, 5/6, 7/8

balancer 2: 2/3, 4/5, 6/7, blank

in your opinion, would this work and be safe? Or are there other issues I am not seeing?

robert-martin asked
Mike Dorsett answered ·

1 Answer

Options for battery balancing 48V bank of 8x 6V batteries

The Victron battery balancer works with 12V batteries. Handling a 48V bank would take 3x balancers.

But, what about a bank consisting of 8x 6V batteries ? Our bank is 8x Crown CR-430 430AH batteries ...

halfwalker asked
Tom Ranson commented ·

3 Answers

Pylontech battery balancing

Just added to US3000C batteries to an existing pair of US3000C batteries. Started balancing operation all commss cables removed as well as lines to inverter. balancing started as expected but after a few hours the 2 existing batteries continue to show discharging but the new batteries are in standby. Restarting the balancing procedure shows that the new batteries are still on 3 LEDs whereas the old batteries are on 5 LEDS. Balancing continues for a few minutes and then they go into standby again. Is this normal and do I just have to wait overnight for balancing to complete. Or is there something I’ve missed.

Roberto Znconato asked
Alexandra answered ·

1 Answer

Battery balancer on 4 x 6 volt batteries

I have 4 x 6 volt AGM batteries wired in series to provide 24 volts , my batteries are now 9 months old and considering a Victron Battery Balancer but i I have a few questions . Is it worth me fitting one now as my batteries are no longer new . A website i found shows one is required for each pair of batteries so i would require 2 units , is this correct . Would they still perform with cables between 1.5 and 2 meters long providing the cables were all identical lengths . Do they produce much heat . I found thi now but can see how it could possibly work when the connections from it go to a set of batteries that are al interconnected , how could it provide extra current to any individual or even pair of batteries , could someone please explain what might appear simple to them but illogical to me .


This is what i have at the moment so not sure if i will be able to use the Victron Banancer

ako asked
JohnC answered ·

2 Answers

Victron battery balancer wire length

Hello I am installing 12 lead carbon batteries in 48v exactly as Victron shows in the battery balancing info sheet. Due to where my batteries sit and the 3 balancers installation location the closest battery is about 2 feet away and the farthest is 10 feet. Do the wires from the balancers all need to be the same length or are they allowed to be different lengths depending how far away the battery connection is?



livibg-on-a-lifeboat asked
Alexandra answered ·

1 Answer

Can't turn of DVCC to balance Pylontech Cells

Hi Guys,

We had some strange high voltage (49,12V) alerts on a Pylontech battery set (6 x US2000C). 3 batteries were a few month's old and 3 new batteries.

We got some internal error's and high voltage alerts, so we contacted Pylontech technical support.

They told us the following:

"OK, please try the following method first:

1. Please use a DC charger with 53.2V and 2-3A to charge these battery together for over 8 hours. This will help balance the cell voltages. This is the best solution.

2. If you do not have a DC charger, please set the inverter in force charging mode for over 8 hours. This will also achieve the effect of cell voltage balance."

I wanted to go with option 2, so I can do it remotely..

Through remote VE configure, i changed the settings in the multi.

But the systems overwrites this... Because I can't turn off DVCC.

I don't think it's possible to do this another way?

So the only option I have is.
Go back to Venus OS 2.73 So I can turn off DVCC.

But the last to stored software versions are 2.87 and 2.85..

So I can't do that remotely? And I still have to go to the location to use a dc charger or use an sd card/usb to put software version 2.73 of venus os in the system.

Or am I missing something?

apacalipto asked
Alexandra commented ·

2 Answers

Initial Top Balancing Lifepo4 24v configuration

I have 4 SOK 12v 206ah batteries going into a 24v 412ah configuration to a Victron MP 3kw/24v

The SOKs have in-built BMS and have been sitting unused (in their shipping boxes) since late last year when I ordered them.

The voltage for each individual 12v battery is currently ~13.07 (two are at .07, one is .06 and one .08).

My question is what would be the best approach to do the initial load top balance? Should I use a bench charger device to bring each one up to proper voltage separately or will the Victron MP do the initial top balance correction even if they are in their ultimate 24v configuration? If the Victron MP will take care of it, are there settings I need to adjust from default for this to occur?

downgrader asked
downgrader commented ·

1 Answer

Cable or busbar for correct midpoint voltage?

In this section of the Wiring Unlimited book, the midpoint connections are illustrated as cables. Should the midpoints be connected to a busbar like the positive and negative cables in order to get the same midpoint voltage across each series?


damien-walker asked
johnsmith edited ·

3 Answers

Mobile + Stationary battery?

Background: I am converting my EV UTV to run on 48V lithium. I also have a 48V off grid solar system. All controlled by various Victron systems.

Question: Does Victron have a device or combination of devices that can detect when UTV is connected, and let it work as an extended battery without risk of a massive power balance war between the two battery banks?

drogos asked

0 Answers

How to keep 4S 2P 12V 220Ah Gel Victron batterybank balanced?

Hello Everybody,

As mentionned in §6.3 of this article

Gel batteries are not suitable for equalization charge.

How to keep balanced a 4S2P with 8 Victron Gel 12V 220Ah batteries without performing equalization regularly ?

How should be wired the battery bank? parallel wiring then serie




or Serie then parallel


In this second solution, wether batterie balancer should be used, each battery string will need battery balancer

What is your feedback about keeping balanced a serie string ?

Thanks for your replies.

cargol66 asked
kevgermany commented ·

2 Answers

Battery balancer

OK so I have 4 12v 100ah lifepo4. They are arranged 2s2p. I get the 24V goes to the positive (in my case a lynx distributor bus bar, similarly I will attach the common to the negative bus bar. I am assuming using the bus bars is OK?

What I am struggling with is the midpoint. I know one wire goes to the first series (either pos or neg). What I am struggling with is the daisy chain to the second series. What gauge wire is that meant to be? My bank uses 4AWG by the way. Is it like the first mid point? Also how don't the batteries get messed up? essentially you are adding an extra parallel connection to the two series banks, right?

That is what is confusing me.

Thanks in advance.

pittsburghred asked
kevgermany answered ·

1 Answer

Can I balance 4 strings of series 4x12(48V) SLA batteries with 3 Victron Balancers?

Can I balance 4 strings of series 4x12(48V) SLA batteries with 3 Victron Balancers?

johnsmith asked
johnsmith commented ·

6 Answers

90 Posts
83 Users

Topic Experts

20 Points