question

bertd avatar image
bertd asked

Voltage oscillating

Hi, I have an MPPT 150/60 to which 4 solar (4×175W, 2/2 in series, then parallel) panels are connected. They should theoretically give ~ 41 V. This it did before I installed Lithium (3×330Ah) and the Lynx Smart BMS. I get strange behavior now: the voltage would increase to ~41V, Amperage woul the drop to zero. This will occur for a few second, the the voltage drops again to ~ 31 A. See screen shot 1000027419.jpg

Any comments?????


Bert

MPPT SmartSolar
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3 Answers
kevgermany avatar image
kevgermany answered ·

Entirely normal. It's the tracking of the MPPT adjusting itself to optimise solar output. LiFePO4 batteries take higher currents, which causes the panel voltage to drop.

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bertd avatar image
bertd answered ·

Thanks! That helps my understanding!

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JohnC avatar image
JohnC answered ·

@BertD

There appears to be two different things happening there. The mppt will track every 10 minutes. They are the ones with regular dips in the V.

The others appear to be complete interruption of the A, the panels then going open circuit. Possibly something to do with the BMS and settings??..

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