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How to wire 3 outputs from a single battery bank?

nezek88

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Jan 2, 2022
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I've got 6 x 48v batteries which I wish to connect to 3 linked single phase inverters.
Its a single battery bank and I need to figure out how to wire three outputs.
The inverters (Growatt SPF5000ES) is communicating with the batteries but I just don't know what's the most correct way to wire it?

Can I wire it like this?

1661418678057.png
 
To do this, you need the batteries tied to a bussbar, and the bussbar tied to the inverters.
Bussbar is the best way to do it no doubt, but...
isn't paralleling the double terminal of the battery already acts like a bussbar?
 
Yeah I'm familiar with it, it doesn't really have the answer this time. or at least not that I can tell.

Considering the batteries are already coming with a busbar and double studded, isn't it essentially becoming one big busbar if I'm paralleling all the batteries using cables?
Page 19 shows the 4 basic patterns.
Using the double terminals on top of your batteries you can do diagonally.
Possibly something resemblinng "halfway" but I've not had enough caffeine to say with confidence.

Inside the case under those double terminals there is probably a little copper bar that joins those terminals.
That means the added resistance of 2 extra joints and a busbar for current that is just trying to get to the next battery.
So more like daisy chaining than like busbars.
IMO the only reason to consider this is if cash is tight.

My preferred topology is common busbars.
connect each battery individually to something like this.

All the other components in the system also get connected to the same set of busbars.

This way each battery has a very similar path resistance to the rest of the system.
Another advantage is ease of maintenance.
Individual batteries can be easily added or removed without disturbing the others.

The systems we make tend to look like a ladder where the busbars are the risers and the circuits are the rungs.
Hope that helps.
 
Inside the case under those double terminals there is probably a little copper bar that joins those terminals.
That means the added resistance of 2 extra joints and a busbar for current that is just trying to get to the next battery.
So more like daisy chaining than like busbars.
IMO the only reason to consider this is if cash is tight.
The busbar is on its way but living in the pacific island it would be another 3-4 weeks until it arrives.

So I'm looking for the right way to switch on the system until we get it...
 
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