Hi Jeff, Mr. Wiles strongly suggests that welding cable not be used for battery connections. You can read up on his guidance here: http://www.nmsu.edu/~tdi/Photovoltaics/Codes-Stds/PVnecSugPract.html Something the NEC is clear about is conductors be used that are listed for that purpose. Welding cable is not usually listed for battery connections. We too have researched the subject and selected Cobra X-flex when we need very flexible conductors - such as for battery interconnections. This cable is listed by UL to MTW / THW with a flame rating of VW-1, in the sizes we use of 1/0 & 2/0. You will need to perform additional research to locate suitable lugs rated for fine stranded wire, and identify a crimping tool that is approved by the manufacturer fro use with the lugs you select. We selected a Burndy YAG26LTC38LD lug to use on 2/0 X-Flex on the ends to mate with our AGM batteries (3/8" SS bolts). Conductors and their approved terminals are rated in a Class system, indicating the number of strands of a size wire, that make up the cable. For example one manufacturer I looked at had the following information: 1/0 conductor Class B = 19 strands Class C = 37 strands Class M (welding) = 2846 Additionally, if you plan to use the fine strand conductor to land on any terminals, be sure the manufacturer approves of this. We found out during an installation that the SMA Sunny Island will not accept the fine stranded conductor we had planned to use to accommodate the conduit run, and had to make a decision to 1) redesign the conduit run to accept a class B THWN cable (tough to bend) or 2) locate and procure a pin terminal adapter that crimps on the X-Flex to adapt it to the manufacturer's recommendation (Ilsco is a source of these). I chose the former due to availability - after many calls, the only sources I could locate of the appropriate adapter had many weeks as lead times. Hope this helps! -Glenn Burt
_____ From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Jeff Blick Sent: Wednesday, March 11, 2009 9:59 AM To: re-wrenches@lists.re-wrenches.org Subject: [RE-wrenches] battery cables Hi wrenches, I have been looking through the codebook for guidance in selecting battery cables for a large UPS system. The code doesn't appear to have much to say about the actual type of wire used. My electrical supplier is suggesting welding cable, but I feel like I read somewhere that welding cable is not appropriate. I know it needs to be 4/0 or larger, just wondering what type of wire others are using for this application. Thanks! Jeff Blick Lead PV Installer Sunlight Solar Energy, Inc. direct: 541-306-4196 fax: 541-322-1911 jeff.bl...@sunlightsolar.com www.sunlightsolar.com This e-mail, and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. Any unauthorized review, use, disclosure or distribution is prohibited. If you have received this e-mail in error, please notify me by replying to this message and delete the original, any copy of this e-mail and any print out made. For additional information about Sunlight Solar Energy please refer to our website at <blocked::http://www.sunlightsolar.com/> http://www.sunlightsolar.co
_______________________________________________ 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