question

paul-cotton avatar image

-0.02V showing on start battery

I have a starter battery, a leisure battery, a DC/DC, MPPT and PV and Multiplus. With all functioning except DC/DC since I isolate the start battery there is a -0.02V showing on the smart shunt for the starter battery. What is this indicating?

battery system voltage
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3 Answers
Mike Dorsett avatar image
Mike Dorsett answered ·

When you isolate the starter battery, are you also isolating the voltage sense wire from the smart shunt? this should go via a small fuse directly to the starter battery. A schematic of your installation would help with a question like this....

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paul-cotton avatar image
paul-cotton answered ·

Mike thank you for the reply. I am not. The sense goes from the shunt to a fuse at inlet of the battery positive the isolation is beyond this nearer the battery.

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paul-cotton avatar image
paul-cotton answered ·

screenshot-20210706-121250-samsung-notes.jpg

Isolation just removes starter battery.


2 comments
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Can we assume that the battery shown is the start battery?

And the connection to the Dc2dc charger is the input?

Isolated Dc2dc converter?


Correct so when isolated dc dc is off.


There is an mppt and a LiPo fully functioning in the remainder of the circuit.