As I read the rule, that 100' in the trench allows you to go 10' above
grade on each side while just worrying about the ampacity in the 100'
section (be sure to check that your terminals are OK). For 200' in the
trench, you're still looking at 10' above grade on each side. The rule
doesn't say that you can only use this exception once per circuit, so
it's fine that you use it once at each end.
On 2011/8/17 12:22, Brian Mehalic wrote:
Question about the 10'/10% rule - the exception states "adjacent
portions of a circuit." How does this apply to an underground conduit
run, where there are two ends exposed to higher ambient temperatures
than the length in the ground?
For example, what if there is 100 feet in the trench, and 7 feet above
grade on either side? Can the exception be applied? How about 200 feet
in the trench and 7 feet above grade on either end?
Thanks,
Brian
--
========================
Brian Mehalic
NABCEP Certified Solar PV Installer™ R031508-59
IREC ISPQ Certified Affiliated Instructor/PV US-0132
PV Curriculum Developer and Instructor
Solar Energy International
Carbondale, CO 81623
http://www.solarenergy.org
_______________________________________________
List sponsored by Home Power magazine
List Address: RE-wrenches@lists.re-wrenches.org
Options& settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules& etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
_______________________________________________
List sponsored by Home Power magazine
List Address: RE-wrenches@lists.re-wrenches.org
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
