Mick,
-2 means 90 degrees C rather than 75. THWN-2 thus means that it is
wet-rated at 90C. That is generally considered Code for arrays,
such as if it is run in NM flex conduit to a traditional module
j-box. The j-box area may be considered to be able to get hot enough
to require 90C rated wire. Nowadays with MC-type module leads,
combiner boxes aren't subject to the same high temperatures on the
THWN as when they terminate in module j-boxes, and the higher
temperature rating isn't generally necessary.
Much of what I'm saying here is older John Wiles stuff.
Allan
On 7/23/2010 10:52 AM, Mick Abraham wrote:
I'm sorry to broadcast my ignorance, but:
Could someone explain to me the significance of the -2
marking? Reply off-list if you wish to save bandwidth...but
other List members may also be wondering...
Thanks,
Mick Abraham, Proprietor
www.abrahamsolar.com
Voice: 970-731-4675
On Fri, Jul 23, 2010 at 10:48 AM, Nick
Soleil <nicksoleilso...@yahoo.com>
wrote:
I have specified THWN-2 for years, but occasionally
will not be able to source it!
Sent from my iPhone
We
went through a similar problem with
some beach communities here in SoCal.
Because of the high humidity (all winter
and summer mornings) they wanted THWN-2 for
all conduit runs (as well as PVC
instead of EMT). At first we were charged a
premium for THWN-2 compared to
THHN. But then we found a source at All
Phase Electrical Supply Burbank CA (a part
of CED) for THWN-2 #10 stranded @
$162.40/k-ft. Brand is En(m?)core
Wire. THWN-2 listing is printed on the
insulation.
-
Peter
Peter T. Parrish,
Ph.D., President
California
Solar Engineering, Inc.
820 Cynthia Ave., Los Angeles, CA 90065
CA Lic. 854779, NABCEP Cert. 031806-26
peter.parr...@calsolareng.com
Ph 323-258-8883, Mobile
323-839-6108, Fax 323-258-8885
_______________________________________________
_______________________________________________
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
|
_______________________________________________
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
