question

thijs-vh avatar image
thijs-vh asked

MPPT 75/15 charging low voltage

img-1721.pngimg-1720.pngimg-1722.pngI have a new installed MPPT smart charger with a 60W panel. I have used in on my boat last week. It seems to be charging enough (have seen 51W charging). The panel gives about 20V but the output to the battery is too low and doesn't reach the voltage settings for bulk mode. I tried to increase this voltage in setting but there's no difference.

The MPPT is connected to the same wires as the battery charger (which charges with higher voltages)

Questions:

1) can I do harm to the batteries charging at low voltages?

2) What could be wrong en how should i get the correct charging voltage?

MPPT SmartSolar
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2 Answers
klim8skeptic avatar image
klim8skeptic answered ·

You are using more power than your puny 60w solar panel can provide,

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thijs-vh avatar image
thijs-vh answered ·

unfortunately there is little power consumption, only 0,3A from consumers. The mppt gives max ca 13,3v and measured directly on the battery it is even lower. I need a bit higher voltage to charge correctly

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klim8skeptic avatar image klim8skeptic ♦ commented ·

"unfortunately there is little power consumption"

That is not what your history is showing..

Your panel managed to harvest 290wh, but that was not enough to get the battery charged.

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