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henriquem avatar image
henriquem asked

MPPT 75/10 - Incorrect load current readings

Hi. I have an MPPT 75/10, powering a load with a very small current, around 0.5A and everything is working as expected, except the measurements of load current I'm getting.

While measuring current with a multimeter I get constant readings around 450mA, with VictronConnect most of the time the readings displayed on UI are 0A and very occasionally I get 0.1A or 0.4A.

I captured the readings through serial port with a 2s interval and as you can see, in here - (Change the file termination to .csv) the great majority of the readings are 0. Does anyone experienced this type of phenomenon with low currents ?Am I doing something wrong ?

Thank you in advance

MPPT Controllers
powerlog13-02-202016-16-02.txt (12.6 KiB)
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3 Answers
Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

I would say the MPPT is not made to make exact measurements of such small currents.

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henriquem avatar image
henriquem answered ·

Thank you for your help M.Lange. After some more experiments I understood why this was happening. Apparently, if the PV is not supplying at least 0.5A, the readings from current are always 0. With a steady suply of at least 0.5A, I have steady readings.

Which doesn't make sense to me, I mean, this basicly means that during the night without solar energy I get no readings of current whatsoever.

Can someone confirm this behavior ?


Best Regards,

Henrique



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gwalsh avatar image
gwalsh answered ·

Was this ever resolved? My setup pulls about 250mA most of the time, then 7A when its got a real job to do. I was watching the Victron Connect app at night (when in my normally low current mode) and noticed it reported the load current was 0A. I was expecting to see 0.2A or 0.3A. Is the controller actually recording the power consumption happening all night long or not? I hope so or the statistics will not be very useful.

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