Hello Tran, This thread now seems headed off in new, un-intended, directions. The question of the relative Benefits and Disadvantages of Recognized Components was not the focus of this discussion.
This particular thread was initiated to discuss my recent awareness, that in UL 1950 / CSA 22.2 No. 950, Third Edition, the previously hard and fast UL requirement for Recognized Insulation Systems (RISs), never before relaxed in my experience (14 years in this business), no longer appears hard and fast. The harmonized UL/CSA ITE Standard now provides for the use of insulation in compliance with CSA 22.2 No. 0, in lieu of RISs, for insulated coils operating above 105 Deg/C. Thus, materials suitably rated as Class B,F,H, N, etc, are useable without having to satisfy RISs requirements. This has great import, both time-wise and $$-wise for manufacturers. It is especially valuable for manufacturers of ITE, located outside of the U.S. who are usually surprised and dismayed when they first learn of the RISs approach to coil insulation. To my knowledge and supported by Egon Varhu's earlier input, only the UL Standards required RISs. That solo requirement now appears to have an alternative. Regards, Art Michael A.E. Michael, Dir. of Engineering Product Safety Int'l 166 Congdon St. East, Middletown CT 06457-8061 U.S.A. Phone : (860) 344-1651 Fax : (860) 346-9066 Email : [email protected] Website: http://www.safetylink.com P.S. In my response to Egon Varhu on this topic earlier this morning, I have just noted a mistake in the last long paragraph. It begins "Within UL, to my knowledge, other than for this provision in UL1446 ......." The standard number mentioned should be UL 1950 (and not UL 1446). Sorry for any confusion I may have caused. :-(
