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valleyokie avatar image
valleyokie asked

MPPT Smartsolar 250/100 charge controller input

Hi All

Im installing my solar arrays for my new system and need to decide the series/parrallel configuration of my panels to suit the input of the 250/100 charge controller.

Im using 330W , 72 cell panels , Voc ( stc) 46V, Isc 9.5A.

I have 2 rows of 4 series connected panels wired in parallel.( 8 total)

This give a resultant Voltage of 184V ( @ STC) and an Amperage of 38A.

There are only 2 wires coming from this array so I can only use ONE input on the charge controller. I read in the manual that each of the three inputs on the controller is rated at 30A.

Im aware that the maximum voltage is critical for the controller but what about the amperage, will the controller handle 38A??

Your urgent help would be appreciated.

Will share info on my installation as I go.

Cheers

Mark

Midlands, Kwazulu Natal, South Africa


MPPT Controllers
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2 Answers
JohnC avatar image
JohnC answered ·

Hi @valleyokie

Use your Imp to do calcs like that (assuming no internal short in your mppt). That would likely be closer to 8A than 9.5A.

And even then, those Amps don't increase in series strings, only when paralleled. With just 2x paralleled, you're well within the rating of the MC4 connectors - maybe 17A at full tilt?

The mppt can handle the A, it's only the plastic MC4 connectors that have the 30A rating.

Rest easy Mark, you'll be fine. And we'd love to hear your progress on a successful installation. :)


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solarhack avatar image
solarhack answered ·

Hi

You should use the Victron MPPT sizing calculator https://www.victronenergy.com/mppt-calculator

You need Watts peak, Voc, Isc, Vmp and Impp. You can also play with the series and parallel settings

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