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progbes asked

MPPT premature float

I have brand new 600ah AGMs and 420 watts solar. BMV has me at 80% SOC but MPPT controller seems to be going into float prematurely. It looks like the battery voltage on the MPPT is quite a bit higher than what the BMV is saying and my guess is that this triggers the Float. MPPT goes from 200 watts down to zero. I then see, within seconds, the voltage drop on the MPPT and the watts cycle up again.

Ultimately the SOC doesn't rise above 80% as the MPPT stays in float.

This can't be normal. Thoughts?



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mppt state
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1 Answer
klim8skeptic avatar image
klim8skeptic answered ·

You seem to have a bad case of voltage drop between the mppt and battery.

Could be from undersized cabling. Could be from loose or dirty fittings/joints. Could also be a bad fuse or breaker.

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