question

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pv-geek asked

BMV 712 and Busbars: Wiring Diagrams

I have an offgrid residential system comprising of 2 strings of PV, with each array connected to different mppt charge controllers (each string has a different orientation), two 51.2V 200AH LFP batteries connected in parallel, a 5KVA inverter and a BMV-712 with temperature sensor.


The BMV shunt can no longer accommodate the negatives of the loads and charges. Same for the positive terminal of the battery. Hence, the decision to use busbars.


1. Is there any other option than using busbars?

2. I would appreciate wiring directions/diagram of using busbars with the BMV with

  • each battery connected to the busbars
  • both batteries paralleled, then a single +ve & -ve connection to the busbars.

3. Where do I connect the temperature sensor to? The busbar, a positive terminal of any battery?

Note: I am not interested in midpoint voltage.

Any other input in this situation will be appreciated.

BMV Battery Monitorbusbar
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2 Answers
Wayne avatar image
Wayne answered ·

The temp sensor needs to be on on the battery -ve.

Single cable from +ve of one battery to the insulated stud/bus, distribute from there.

  1. Single cable from -ve of the other battery to the batt side of the shunt, Single cable from load side of shunt to ins stud/bus distribute from there
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kevgermany avatar image
kevgermany answered ·

Take a look at the Victron Lynx distributors as an alternative. Essentially they're extendable fused busbars, but with some clever features.

On busbars, temp sensor remains where it is. I think yours goes on the positive terminal, but check as some Victron temp sensors are for negative terminals. I just installed a negative busbar on the load side of shunt. Positive side went directly from batteries to my battery isolator/fused distribution side, I didn't need one there.

But best get dealer professional advice if you're unsure.

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