All,
Because of the high organic content in Kapton (polyimide) you must always use Comparative Tracking Index (CTI) IIIb in your spacings calculations for IEC-based standards; UL equivalent PLC is 4 (see IEC 60112, UL 746). Information on many individual materials and their respective CTIs can be found at http://database.ul.com/cgi-bin/XYV/template/LISEXT/1FRAME/index.htm and I especially like to research materials on http://www.matweb.com/ or http://www.goodfellow.com/ Regards, -doug Douglas E. Powell Senior Compliance Engineer Corporate Product Compliance Advanced Energy Industries, Inc. 1625 Sharp Point Dr. Fort Collins, Colorado USA 80525 _____ From: [email protected] [mailto:[email protected]] On Behalf Of Price, Ed Sent: Wednesday, October 24, 2007 6:49 AM To: [email protected] Subject: FW: Kapton I had recently asked about cautions regarding the use of Kapton (polyimide) insulation for wiring used in manned aircraft. John Zenter sent me this email, and I have his permission to share it with our list. Ed Price <mailto:[email protected]> [email protected] WB6WSN NARTE Certified EMC Engineer & Technician Electromagnetic Compatibility Lab Cubic Defense Applications San Diego, CA USA 858-505-2780 (Voice) 858-505-1583 (FAX) Military & Avionics EMC Is Our Specialty _____ From: "Zentner, John C CTR USAF AFRL/RYRA" <[email protected]> List-Post: [email protected] Date: Mon, 22 Oct 2007 07:45:53 -0400 Subject: RE: Kapton The big issue with Kapton-insulated wiring was carbon arc tracking, where an electrical arc initiated by a short circuit can travel along the wire due to carbon deposits. That issue was with MIL-W-81381 constructions where the insulation material was purely Kapton (chemical name is polyimide). That construction has been largely replaced by hybrid constructions that are combinations of Kapton and Teflon that suppress arc tracking (see SAE-AS22759 in place of MIL-W-22759). The issue with 81381 was only with power wiring. Kapton is routinely used in commercial items for high-voltage applications and printer ribbon cable among other uses. John Z This message, including any attachments, may contain information that is confidential and proprietary information of Advanced Energy Industries, Inc. The dissemination, distribution, use or copying of this message or any of its attachments is strictly prohibited without the express written consent of Advanced Energy Industries, Inc. ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
