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chisom-onuegbu avatar image

Using two battery balancers for 4 parallel strings

I need some help with proper configuration of my victron battery balancers for 4 parallel strings of 24 volts. My set up has a Quattro 5000/24v and eight(8) Trojan SAGM 205 batteries configured in 4 strings of 24 volts (820AH)

I am using two battery balancers, as I read one unit can only balance up to 3 parallel strings. So I have separately connected the midpoints of the first two parallel strings and the next two parallel strings. schematic is below.


Thanks.


parallelBattery Balancer
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3 Answers
Herve RV Nizard avatar image
Herve RV Nizard answered ·

One question to those having already seen the battery balancer : Does it come with the colored wires in the box ?

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Herve RV Nizard avatar image
Herve RV Nizard answered ·

I am very interested by this point. I am designing a similar system with 16x 220 gel 12v batteries in 4s4p. In 48v. Was wondering what diagram for the balancers too, and would really appreciate some input on: 1. Are balancers really useful for 4p of 12v. Are 12v gel batteries really "balanceable" ? 2. What do you use to combine the 4+1 lugs ? Anything easier to find (in my remote island) than a coppper bar ? Thanks a lot .

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launacorp avatar image
launacorp answered ·

I read the manual and found one thing in the "installation" part under point 2.


It says for 2 cell... and for 3cell.. "..,etc."


So I wouldn't say it's limited to 3 cells in parralel. Just the compensation-current gets smaller and smaller.


But for MY technical understanding your Setup should be okay. But for my opinion it should be okay too, if you set up a common middlepoint for all your parralel strings an then parralel the balancer too, so you have a "virtual" balancer capable of delivering 2A to balance.


If the balancers are not equal each other in some millivolts with turning on or off that should't be a Problem in your configuration.


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Thanks @launacorp. I guess setting up a common midpoint for all 4 parallel strings is how Victron originally intended but the documentations on the battery balancer are not as detailed or extensive as the other products. Or perhaps I dont have as much experience to interpret the existing documentation! :) :) And I like the idea of connecting all midpoints as this will also help me monitor the collective midpoint with a BMV. I have updated the drawing now below.


Perhaps @Johannes Boonstra (Victron Energy Staff) or @Guy Stewart (Victron Community Manager) can take a quick look and confirm for us.


Please help out.



Thanks @launacorp . Yes, I think connecting all 4 midpoints together must be Victron's original intention even if I am using two battery balancers for my set up. I have updated the schematic to show this below.


Perhaps @Johannes Boonstra (Victron Energy Staff) or @Guy Stewart (Victron Community Manager) can provide a firm confirmation that this new arrangement is the correct setup.

Thanks in advance.