question

clnewman5566 avatar image

Are my BMS and Solar Charger working properly?

I have the Smartshunt networked with an MPPT 150/70 charger. There are three 325W solar panels, and four UT1300 105ah lithium batteries.

I'm not sure the charging system is working properly. Please see the photos. Is what I'm seeing normal ? Why isn't the BMS showing a positive rate of charge?

The battery load looks about right (10.77A), but shouldn't I be able to see a net increase in SoC? Are my Victron devices configured incorrectly? When I charge from my generator, the BMS shows it's charging.


We're full time RVers, and it's imperative I get this right. TIA


Edit: I don't know why the charge controller Screenshot isn't showing, but there's a link for it.screenshot-20210603-094438.jpg



mppt smart solarsmart shunt
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1 Answer
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

As always check your wiring of the SmartShunt.

I guess the MPPT negative is connected to directly to the battery instead of the "load/charger" side of the shunt.

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You may be on to something there. I installed the Shunt myself, but the RV dealer installed the MPPT. I followed the Shunt instructions to a T, but didn't bother to check the MPPT.

Would simply moving the MPPT negative to the load side of the Shunt probably solve the problem?