equipment grounding conductors [RE-wrenches]

[Larry Crutcher, Starlight Solar]

Drake Chamberlin wrote:
> 
> Hi Larry,
> 
> This is the issue of the size of the equipment grounding conductor, and 
> if we can use EMT conduit for an equipment ground as permitted by 
> 250.118.  The equipment grounding conductor size for PV is covered in 
> 690.45.  
> 
> Thanks,
> 
> Drake 
> 
> 
> Larry Crutcher, Starlight Solar wrote:
> > 
> > 
> > Drake Chamberlin wrote:
> > > 
> > > Correction:
> > > 
> > > We size the wire for 125% short circuit current.
> > > 
> > > Drake 
> > > 
> > 
> > Drake,
> > 
> > The 125% rule is correct for determining the ampacity of your source 
> > circuit current. However, you must add an additional 125% to size the 
> > conductors and the overcurrent protection. This means you need 156% of 
> > the Isc for all PV wire runs and the fuses or breakers protecting each 
> > string. Also, do not forget to derate for temperature.
> > 
> > Larry Crutcher
> > Starlight Solar
> > Yuma, AZ
> > Renewable Energy Products Powered by STARLIGHT



Ohhh...I have always used the 1.56 rule for my ground conductor as well 
as the current carrying conductors. Guess I can save a buck on my next 
install! More like $50 with copper prices where they are.

Thank you for the education.

Larry


- - - -
Hosted by Home Power magazine

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

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

List rules & how to change your email address: www.mrsharkey.com/wrenches/etiquette.php

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

Moderator: michael.welch at homepower.com
--^----------------------------------------------------------------
This email was sent to: michael.welch at re-wrenches.org

EASY UNSUBSCRIBE click here: http://topica.com/u/?bz8Qcs.bz9JC9.bWljaGFl
Or send an email to: RE-wrenches-unsubscribe at topica.com

For Topica's complete suite of email marketing solutions visit:
http://www.topica.com/?p=TEXFOOTER
--^----------------------------------------------------------------