Carrie, From a high rel perspective in the Aerospace Industry, any part rated one watt or greater had to be isolated from the PWB laminate surface.This could be accomplished by a thermal plane on the suface, sleeving the part or lifting it off the surface. This goes back to the days when lower Tg FR4 materials were in use and may have been more of a problem.In working with IPC, it was felt that the compatibilities of the parts, materials used and the resultant exposures to thermal excursions should be assessed prior to production.Any unique requirements should be AABUS (as agreed between user and supplier) and therefore is no longer part of the requirements definition.It it was to be anywhere now, it should be in 6011 or 6012 as design related criteria. Dewey > -----Original Message----- > From: Morse, Carrie [SMTP:[log in to unmask]] > Sent: Thursday, March 11, 2004 7:27 AM > To: [log in to unmask] > Subject: [TN] Can't remember a darned thing! > > Since, for some reason, I can't remember a darned thing lately, I was > wondering if someone could tell me WHERE within all of our IPC specs I > can find where it specifies at what wattage we need to start raising > resistors off the board (ex: 1W, 1.5W?) > > Thanks, > Carrie > > --------------------------------------------------- > Technet Mail List provided as a service by IPC using LISTSERV 1.8e > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to > [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to > [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 > for additional information, or contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------