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dalane avatar image
dalane asked

Need Help Understanding MPPT Solar "Gauge" Icon

We have 4 Victron MPPT 75/15 controllers, that normally read approximately the same output per their Solar "Gauge" Icons via the Bluetooth dongle. Today, however, 3 of the 4 are mostly reading "0 watts" while the 4th is constantly showing 44-55 watts. Our new ReLiON battery bank is at 95% SoC, it's a bright sunny day, ~70F, and all 4 panels are receiving the same sunlight with respect to angle, clouds, etc. Periodically, the 3 gauges in question will bump up to 3-8 watts and hang out there for awhile, then fall back to 0. At this moment, for example, #1 = 3 watts, #2 = 4 watts, #3 = 51 watts, and #4 = 5 watts. Please help me understand what's going on.

MPPT Controllers
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2 Answers
esteban avatar image
esteban answered ·

I'm going to guess that they have gone into Float mode which is lower than your battery voltage and so are not passing any power. The single one has not entered float, possibly due to different float settings or is reading different state of charge. The fact that they bump up to a few watts now and then indicates that they are letting a bit of power through as the battery voltage drops and allows for some more charge, then it reaches equilibrium again.

I've seen my single 75/15 MPPT do the same and wondered, then figured this is the case.

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Paul B avatar image
Paul B answered ·

Basically I would suspect Esteban is correct

I presume that you have set the battery type to Lithium on all the Mppt Chargers.

As you have a bluetooth dongle you change the setting in the settings menu under battery then Battery preset

select preset scroll down and select lithium iron phosphate

Also under history you should be able to see the max voltage that each charger see's



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