[RE-wrenches] calculating low string voltage

[Comet Systems]

As far as I know, the temperature coefficient holds true whether you are
increasing or decreasing the temperature around the STC temperature of 25C.
Of course, there is going to be a point at which it goes non-linear, but
that is not stated.

On Tue, Nov 29, 2011 at 3:58 PM, Scott McCalmont <
re-wrenches at scottmccalmont.com> wrote:

> Usually you increase the temperature above ambient by an amount which
> depends on the mounting method. Close to the roof is +35 degrees C, more
> than 6 inches above the roof is +30 degrees C, and pole or ground mount is
> +25 degrees C.
>
> Scott
>
> On Nov 29, 2011, at 11:48 AM, Kirk Herander wrote:
>
> I am in debate with a PE over calculation of low voltage of a series
> string on a hot day. He insists that an arbitrary high cell temp is
> factored in, not just ambient temperature. Could someone please give an
> accepted formula for this calculation? Thanks. I cannot find a clear
> reference to low voltage calculation on a hot day (but every reference
> material is clear on how to calculate high voltage on a cold day).****
> ** **
> Kirk Herander****
> VT Solar, LLC****
> dba Vermont Solar Engineering****
> NABCEPTM Certified installer Charter Member****
> NYSERDA-eligible Installer****
> VT RE Incentive Program Partner****
> ** **
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-- 
Chris Mason
President, Comet Systems Ltd
masonc at cometsystems.co
www.cometsystems.co
Cell: 264.235.5670
Int: +1305.767.2094
Skype: netconcepts
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