Just to add my "2 cents" to this discussion. CTI etc. after manufactured into a finished PCB is actually more important than the CTI of the basic laminate itself. That is one reason why one should use PCB vendors who have their process UL recognized (and use the recognized logo on the finished product for identification). The PCB fabrication process, solder mask, etc. can affect both CTI and flammability greatly.
Comments are personal and do not necessarily reflect corporate opinion. Harold Leipold Siemens EC Princeton, IN Tel 812-386-2161 Fax 812-386-2616 [email protected] on 02/19/98 02:48:17 PM Please respond to [email protected] To: [email protected] cc: [email protected] (bcc: Harold Leipold/PRI/SEC/US) Subject: Re: Comparative Tracking Index Hi Rick: You ask about CTI for printed wiring boards, and typical values. According to the UL Yellow Book, CTI is indicated in volts. In glancing through the UL Yellow Book, very few board manufacturers have submitted their boards for CTI. The few that have submitted, have CTIs in the range of less than 100 up to about 250. A very few manufacturers can provide boards with CTI exceeding 600. Best regards, Rich "Life is ours to be spent, not to be saved." -- D. H. Lawrence ------------------------------------------------------------- Richard Nute Quality Department Hewlett-Packard Company Product Regulations Group San Diego Division (SDD) Tel : 619 655 3329 16399 West Bernardo Drive FAX : 619 655 4979 San Diego, California 92127 e-mail: [email protected] -------------------------------------------------------------
