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winston-hung avatar image
winston-hung asked

Unable to measure voltage on starter battery

Not sure if I wired up my battery monitor wrong or my shunt is faulty. I want to measure the voltage of the starter battery. I have the postive cable on my starter battery and it's plugged into the B2 of the shunt. The negative of the starter battery is connected to my mppt then goes to my shunt on the load side. On my display it shows 0.03V (pretty much zero). I have checked the settings and it's set to starter battery. If I switch the B1 and B2 around my voltage changes and is roughly correct when I check it with a multi meter.

Is my wiring correct or have I wired something wrong or is my shunt faulty?

BMV Battery Monitor
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Alexandra avatar image Alexandra ♦ commented ·

@Winston Hung

Is there a reason why you have wired the battery to the mppt?

As a step for troubleshooting try wiring it to the shunt and seeing if that works. Following this diagram...

https://community.victronenergy.com/storage/attachments/833-1547720488224.png

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Jesse avatar image Jesse commented ·

So this is a dual battery setup, and you're treating the starter batter as another load, maintained by the MPPT?

I'm not quite sure I can follow your description - perhaps a diagram if possible?

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1 Answer
Wayne avatar image
Wayne answered ·

In the settings area there are several options for the B2 terminal, if it is not already, set it to aux battery, also if the two battery banks are not common neg, you may need to bond the negs of the two banks to allow the function to work.

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