question

antjam avatar image
antjam asked

SmartSolar MPPT 100/20 Minimum Vmp?

Good day,


I have a single panel with the following specs:

Pmax: 260W

Voc: 38.4V

Vmp: 30.72V

Imp: 8.47A

I am looking to get a SmartSolar MPPT 100/20 charge controller to charge a single 12v 100A Gel battery for my caravan. I was told by the technical support chap at the local distributor that the Vmp of 30.72V is too low for the MPPT charger to work effectively at charging a 12V battery and that I would require a Vmp of at least 60 - 70V to make the SmartSolar 100/20 work efficiently - is this correct?

MPPT Controllers
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2 Answers
Mark avatar image
Mark answered ·

I disagree & think that it would work fine - there is a reasonable 'buffer'.

The Voc is more relavent in relation to the MPPT 'wake up' that is Vbatt +5v & it's a fair amount higher (about 20v higher).

Yes higher voltage would be a tad better but there should be no issues with your proposal.

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wkirby avatar image
wkirby answered ·

I agree with Mark.
That is a perfectly acceptable Vmp for a 12V system Voltage.
I don't know why your distributor told you that. He'd be right if your system Voltage was 24V.

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