Sir Based on *anecdotal* experience, use of PWB trace for P.E. is common only in SMPSs that have no chassis or surrounding frame. For example, my employer, mostly for the reasons published in this thread, does not use a PWB-only P.E on any (AC/DC converter) SMPS. While my employer offers some frame-less DC/DC converters that do have a "de-facto" PW-based P.E., none are intended for the TNV enviroment.
And, AFAIK, all Class 1 SMPS should have a chassis-based P.E. R/S, Brian -----Original Message----- From: John Woodgate I read in !emc-pstc that Rich Nute <ri...@sdd.hp.com> wrote (in <200302051810.kaa05...@epgc264.sdd.hp.com>) about 'EN60950 protective conductor test' on Wed, 5 Feb 2003: >In my experience, PWB PE circuits are common, >and most difficult to obviate. So says our SMPS expert on the national committee. Well, chacun à son gout: I'll do my best to avoid them entirely. -- Regards, John Woodgate
