"Real" Sun Hours [RE-wrenches]

[Travis Creswell, Ozark Solar]

My second question of the day.

Noticing the high module temps I am seeing even on cool days I am wondering
about the accuracy of Sun Hour numbers.  

I use the DVM on my C40 to make a crude calculation of the daily sun hours I
am getting.  Of course, it's accuracy is questionable and commonly I have
found the C40 DVM's that I've installed to read amps about 10% low.  Voltage
is usually right on.  Mine is no different.  Simply, I divide the rated amps
of my array into the amp hours for that day and that tells me how Sun Hours
I got.   Currently I have only part of my array installed so I only have 7.1
amps (Four Astro power 120's at 48 volts).  

But what I just realized about this number is that it factors everything in,
including a de-rate for heat and actual insolation.  Are these things
already factored in to the commonly published Sun Hours numbers?

Travis Creswell
Ozark Solar

- - - -
To send a message: RE-wrenches at topica.com

Archive of previous messages: http://www.topica.com/lists/RE-wrenches/

List rules & etiquette: http://www.mrsharkey.com/wrenches/etiquete.htm

Check out participant bios: www.mrsharkey.com/wrenches/index.html

Hosted by Home Power magazine

Moderator: michael.welch at homepower.com

==^================================================================
EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9
Or send an email To: RE-wrenches-unsubscribe at topica.com
This email was sent to: michael.welch at homepower.com

T O P I C A -- Register now to manage your mail!
http://www.topica.com/partner/tag02/register
==^================================================================