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friaras avatar image
friaras asked

Where do I hook up the Red wire from the aux terminal to monitor mid point voltage on a 48v LiPo battery 8X12v in series parallel?

There are 4 batteries per bank hooked up with bussbars one positive and one negative, the shunt is in the negative side of the banks where do I connect the wire for midpoint voltage? The batteries are hooke up in series parallel in 2 banks of 4 each, they are joined by a positive and a negative bussbars and a cable from each bussbar pos and neg go to the all in one inverter. The shunt is in the negative side right before the negative bussbar, I understand that is supposed to go on the positive terminal closer to the negative bussbar? Or in other words from left to right left being the positive bussbar and right being the negative bussbar, the wire should go to battery number 4 on the positive terminal of that battery? What about the other battery bank? Will that work with the wire connected to just one battery on just one of the banks?

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klim8skeptic avatar image klim8skeptic ♦ commented ·

Wiring Unlimited has a pretty good diagram / description on page 21.

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kevgermany answered ·

You need to join the mid points where you're expecting the 24V. Make sure this connection is fused. Ideally look at battery balancers. Strings of LiFePO4 like this should be balanced within the strings. You'll need two balancers

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klim8skeptic answered ·

I am seeing a 6 x 12v battery - 36 volt system.

I am also seeing an inverter marked as a 36v model.

You cant get mid-point voltage monitoring on that setup.


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johanndo answered ·

Between battery 2 and 3, it is called mid point voltage, because it is in the MIDDLE of the chain, doesn't it make sense to you, 2 batteries up and 2 down - middle, half the voltage?

Are you sure your Chins batteries are speced to be wired in series? You need specific BMS designs to do this safely, as they can run in overvoltage conditions in a string easily and become unstable.

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