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David avatar image
David asked

Do I use STC or NOTC Voc (or Vmpp) figures when sizing MPPTs

To ensure we dont damage MPPT with upper Voltages, do we use STC or NOTC (3-5v lower) and do we use Voc or Vmp. I dont want to be unnecessarily over cautious because we like to use the 150/100 where we can but will move to the 250/100 if required.

Thanks

David

MPPT SmartSolar
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1 Answer
Vance Mitchell avatar image
Vance Mitchell answered ·

Normally I would use the STC figures and also input the temperature coefficients as well.

You want to ensure that you never exceed the maximum input voltage (Voc x number of panels in series) and should leave a bit of headroom just in case.

The MPPT calculator is your friend here.

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