Larry, I don't think the relationship of AWG size to ampacity is a linear curve, so while that "rule of thumb" may be pretty good, you can't always count on it. I would use the circular area column in NEC Chapter 9, Table 8 for an easy, quick way to compare two of one conductor vs. one of another.
Of course there are other code issues regarding parallel conductors... Cheers, -Nathan -- Nathan J. Stumpff NABCEP Certified PV Installer #091209-175 NABCEP Certified Solar Heating Installer #032412-14 Project Manager | Arctic Sun, LLC nat...@arcticsun-llc.com <mailto:nat...@arcticsun-llc.com> | (907) 457-1297 www.reina-llc.com<http://www.reina-llc.com> | www.arcticsun-llc.com<http://www.arcticsun-llc.com/> [cid:image001.png@01CE3115.44031510]<http://www.facebook.com/ArcticSunLLC> From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Larry Crutcher, Starlight Solar Power Systems Sent: Thursday, April 04, 2013 8:51 AM To: RE-wrenches Subject: [RE-wrenches] Combining conductors Wrenches, Here's a tough one for me to understand. I am installing 2 volt AGM batteries. There are two terminals for each battery polarity. I have some height limits so I need to use the minimum wire size. Here's my question: If I combine two identical conductors, what is the equivalent single conductor size? I found one "rule of thumb" that says doubling like conductors creates a AWG decrease of 3. Example: two #2 will be equivalent to 2/0. Is this true? Thank you, Larry Crutcher Starlight Solar Power Systems
<<inline: image001.png>>
_______________________________________________ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Change email address & 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