Panels VOC & ISC
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Goboatingnow
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In general no but these figures are based on a given specified level of irradiance , more irradiance and these numbers change
yes they can. they increase with low temperature. check you panel temperature coefficient spec.
timselectric
If I can do it, you can do it.
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Yes they can. You should make sure that they don't.
Once the magic smoke gets out, you can't put it back.
OzSolar
Whatever you did, that's what you planned.
Voc goes when temp goes down. It is important to design for this.
Isc goes up when temp goes up but it's so small I don't think it's ever designed around.
Goboatingnow
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Incorrect you can safely exceed Voc or Isc
The standard test condition for a photovoltaic solar panel or module is defined as being 1000 W/m2 (1 kW/m2) of full solar noon sunshine (irradiance) when the panel and cells are at a standard ambient temperature of 25oC with a sea level air mass (AM) of 1.5 (1 sun). Moreover, ISC is the short-circuit current at STC and VOC is the open-circuit voltage.
littleharbor2
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I've seen many times substantial increases of isc. on cool partly cloudy days. Look up "Cloud Edge Effect"
OzSolar
Whatever you did, that's what you planned.
That's a good point. But have you seen it exceed the "rated Isc" at NOCT?
I've observed it many times on dozen of different arrays but all I've ever seen it do is get the array almost to it's rated wattage for a few seconds. Just my 2 cents.
littleharbor2
Solar Addict
Yes I have. It's only for a brief moment as the sun's rays bounce off the clouds .
Used to sell a lot of used solar panels and would always meter them for the buyers. So I had many opportunities to see this happen while doing a short circuit current test. I had the panels aimed directly at the sun which gives the best current as well.
OzSolar
Whatever you did, that's what you planned.
Very good then. I've never done it one panel at a time, just been watching the meter on the system when the cloud edge happens. IE: 3000 watts worth of panels are running at 2500 watts which is the most they ever do and see it climb to 2900 watts for a few seconds. Was the angle perfect? Probably not.
timselectric
If I can do it, you can do it.
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Not if you want to continue using the SCC. At some point it's going to give up the smoke.
But good luck trying it.
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