question

thub avatar image

How do I install BMV-702 with two 12v batteries in parallel?

I am confused by the Installation Guide for my new BMV-702 to be setup with an auxiliary battery. The Guide shows both battery positive terminals connected “to load”. I only have a single wire supplying power to my travel trailer. Don’t I need a battery cable connecting the two 12v battery positive terminals in order to get the capacity benefit of having the two batteries in parallel? I prefer to connect the load wire to the auxiliary battery – but does it matter?

BMV Battery Monitorinstallation
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1 Answer
Paul B avatar image
Paul B answered ·

if in parralle then the negative leads from BOTH batteries go the the battery side of the shunt

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So instead of connecting the negatives on each battery to each other both go to the Shunt? do you have a diagram to explain this?

https://www.victronenergy.com/upload/documents/Wiring-Unlimited-EN.pdf

wrong:
1611907788270.png

right:
1611908019497.png
The yellow point is where the Shunt should be.
We mostly use the "diagonally" wiring.

1611907788270.png (61.9 KiB)
1611908019497.png (118.2 KiB)