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xpatrik avatar image
xpatrik asked

77V On pv input at night? (MPPT 150/45)

Hi, I noticed a very strange issue on my solar system tonight. My mppt (150/45) Seems to report aroud 77V on pv input at night. There is no light near the panels so it's not possible to be at that voltage at night. This is the first time this has ever happened.


This is a bit of a remote system (just not at my home) So it's not that easy to measure the voltage at night with a multimeter. Let me know if that is needed or a other solution to fix this problem.


This is my vrm share link if anyone wants to take a look at the advanced data and maybe find the issue (https://vrm.victronenergy.com/installation/191449/share/5632938d)


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MPPT ControllersSolar Panel
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xpatrik avatar image xpatrik commented ·
Update!, The 77V issues seems to have resolved after turning the charging on and off couple of times trying to fix the 300W/5A charging limit for some reason. So the random voltage at night is not there now. But as i said i still have the issue with the only 300W/5A charging. I will retest tomorrow!
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xpatrik avatar image xpatrik commented ·

Also noticed a very low power output from mppt.

I have a grid tie that has 385Wp of panels and is producing 132W

And the mppt has 3060Wp of panels and is only producing 330W. I can see that its not doing proper mppt because the pv voltage is still very high (my mppt voltage is around 80-90V). Yes i know that my battery is full but i have enabled to export dc power to grid and its still not doing it. And yes it worked this way before without any issues with battery being full and exporting the extra power

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Alexandra avatar image
Alexandra answered ·

@xPatrik

That should definitely not be the case. I see it started a few days ago.

Is the mppt switching to an off state at night?

Seems like a diode may not be working correctly. It would be something an RMA would clear up.

The only test you would be able to do remotely is switch off the charger at night and see if anything changes. But wont help with the physical removal, or other tests that would need to be done on site.

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xpatrik avatar image xpatrik commented ·

It WAS siwtching to off state at night but as oyu can see last night when i noticed the 77V it did not switch. Is stayed in Ext Control (The system is ESS).

Also if the diode is not working correctly how would it have 77V on input if the battery is 58V?

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Alexandra avatar image Alexandra ♦ xpatrik commented ·
@xPatrik

No idea there. But good news the good old switch of and switch back on fixed it ;)

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MPPT Product Page

MPPT Error codes

MPPT 150/60 up to 250/70 Manual

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