Hi Greg:
> I have been trying to think of an example where the standard (IEC > 60950-1:2001) requires a flame retarded material where no > possibility of flame exists and cannot come up with one. I had a product where the main PWB was vertical and against one side of the product. The other side of the product was about 15 inches away from the board. (This type of construction is quite common in ink-jet printers!) There was no question the plastic side next to the board was required to be flame-retardant material. However, the other side, 15 inches away from the PWB, had no chance of ignition from any failure on the PWB, but the standard requires the side to be flame-retardant material. The power supplied to the PWB was not LPS, but was not much more than 100 watts. If you can imagine a 100-watt light bulb 15 inches away (in a horizontal line) from a vertically-oriented plastic material, I believe you can easily conclude that the radiated thermal energy at 15 inches is not likely to ignite the plastic material. In another case, the product was large and therefore the enclosure was required to be 5V. No problem. However, the mains switch was mounted on a small V0 part that was in turn attached to the 5V part. To comply, the small part had to be changed to 5V. Not quite to the point of your request, but these examples show that constructional standards do not allow for innovative design alternatives. Best regards, Rich - 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 emc-p...@ieee.org 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 emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
