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> From: John Woodgate > Sent: Wednesday, August 18, 2004 1:55 PM > > Peter L. Tarver <[email protected]> writes > > >There you have it. You may dice it coarsely of > finely, but the above > >represents a *National or Group Difference* and > should be properly > >documented in both the EN version of any and all > effected standards > > Consider that it takes time to amend a standard > (a minimum of 3 years, > normally). I am not involved to any significant > extent with the > maintenance of EN 60950, but Ah, a hint of agreement. Just a hint. > > and > >in the CB Bulletin. > > I have no idea why it wasn't in the CB Bulletin. > Possibly just human error. I suspect it's political, which might be thought of as erring at the "highest" level humanly attainable. The issue of MOVs has been around for a very long time, at least as long as the CB Scheme has existed and probably almost as long as the technology, and, at times, gets extraordinary amounts of attention in compliance quarters. The internal fuse size issue seems without technical merit, especially if the fuse is not user replaceable. After all, the 60950 and 60950-1 state that, for Pluggable Equipment Type A, the building installation is considered to provide backup short-circuit protection. I would very much like to better understand the rationale for this one. > >Simply because factions within the EU chose to > >refer to this rose by another name and claim > it's existence is the > >result of another process (ie, through CENELEC > and its membership), does > >not change the ultimate effect and amounts to > rationalization. > > I'm not quite sure what you mean by that. I mean that such issues are not accepted as National Deviations or Group Differences, in spite of clear evidence to the contrary. I am not debating the technical merits of the issue, only that, in considering compliance on a country-by-country basis, there are some requirements more onerous than others for specific countries identified explicitly in OSM Decisions. Treating them as other than requirements defining the least common denominator for a construction feature amounts to folly for a manufacturer. Both of the above points ("not national deviations" and "CENELEC process") were used in this thread to disagree with my position. > I believe that MOVs to ground are not allowed in > one or more N. American countries. It's your turn to name one. They are accepted in the US and Canada, based on the certification processes in place for them in those countries. There may be specific product standards that state otherwise, but I don't know which, if any. Other than Mexico, I'm not aware of any other North American country with much of a compliance regime. I don't know Mexico's position on MOVs. Regards, Peter L. Tarver, PE [email protected] This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. IEEE PSES Main Website: http://www.ieee-pses.org/ To post a message send your e-mail to [email protected] Instructions for use of the list server: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
