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dgmar-ni avatar image
dgmar-ni asked

MPPT 150/85 remains in float

Hello,

I have an OFF GRID system with two Blue Power MPPT 150/100 and MPPT 150/85. It turns out that MPPT 150/85 remains in float stage always while MPPT 150/100 is on bulk and batteries don't reach 100% SOC.

MPPT 150/100 charging normally:

MPPT 150/85 always on float:

Both controllers have the same FW version.

Please advice.


MPPT Controllers
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3 Answers
Elimac avatar image
Elimac answered ·

It is noticeable on your pictures that the voltage seen by the two MPPTs is not the same. The one in float sees higher value. Are they connected to same battery? What do you have in between? Any circuit breaker or fuse? Check that device if you have it.

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neoneddy avatar image
neoneddy answered ·

I had the same issue when I had a loose terminal from my solar controller to battery bus bar.

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jeremie-simonet avatar image jeremie-simonet commented ·

HI, I checked my terminals and use a multimeter to test on the MPPT connection what voltage is displayed. It says about 11.30V and MPPT stays on float.

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Elimac avatar image
Elimac answered ·

Yes, as @neoneddy said, the connections are worthwhile to check. If the MPPT sees open circuit, it could be the cause for the problem.

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jeremie-simonet avatar image jeremie-simonet commented ·

Hi, I seem to have the same issue. What do you mean open circuit?

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