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greg-griffin avatar image
greg-griffin asked

SmartSolar Chargers MPPT 100/50 not outputting set voltage

This seems to be a very common question that many people have. Perhaps there is a problem?


I have 4 SmartSolar MPPT 100/50. The input voltage is 74V+-. I'm charging 12V LFP battery bank. I've gone to custom config for each MPPT and made sure that all output settings are at 14.6V (recommended for these). There is no float, bulk or anything. The BMS on the batteries takes care of that.


Problem is that when I connect directly to each MPPT, the output voltage is stated down in the 13's. Why? Shouldn't the reported output be 14.6v whenever there is an input in the 70v's. Am I missing something? I don't want to be charging these new LFP's at a lower voltage than recommended.

MPPT Controllers
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klim8skeptic avatar image klim8skeptic ♦ commented ·

Im not sure holding the battery at 14.6v is a good idea.

What battery do you have.

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greg-griffin avatar image greg-griffin klim8skeptic ♦ commented ·

LFP from BigBattery. They specifically state a charging voltage of 14.6

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2 Answers
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spanner answered ·

The voltage increases as the charge status increases - it wont charge at 14.6v right away - see clip from mine below. Mine charges up to 14.2v
1615894123350.png




1615894123350.png (21.1 KiB)
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greg-griffin avatar image
greg-griffin answered ·

OK. So the MPPT is not showing the output voltage but the battery voltage? Funny, because on the app and connected to BT, it says "OUTPUT VOLTAGE". Might be nice if it showed output and battery and separate so I know at what voltage it is currently trying to output. It also is showing in my graph that the battery was at 15v!!! I never asked it to go that high, turned off EQ. Just not convinced they are doing what I want.


I do have the Victron BT shunt and connected to the network. Wondering if that value is overriding or being used instead. Will test some more today.


1615894784619.png


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