Hi Doug! Ignoring the EMC questions (as I can safely do, being a product safety division engineer at TUV!) the enclosure of the open frame supply would have to meet the same safety requirements as any other enclosure around a hazardous voltage circuit. The creepage and clearance distances between the exposed hazardous voltage components and the accessible surfaces in finished product would have to be adaquate.
Of course, if you are just producing the filter that is not your concern! Regards, Frank West Sr. Engineer TUV Rheinland NA --- "POWELL, DOUG" <[email protected]> wrote: > > Hello once again, > > I have already received a number of replies to my > query indicating that the > metallic enclosure is required for low inductance > coupling to the components > or to prevent radiation between circuits within the > product. This is not my > question. > > Please remember that one of the criteria that I > described for the open frame > is the passing all applicable EMC tests. This means > that the open-frame > design that I propose meets both radiated and > conducted emissions levels, > without the metallic box. My questions deals more > with why is the enclosure > required if product passes the tests without it. In > the past I have > designed a few products with a simple PCB for > emissions control. I > compensated for the internal re-radiation problem. > > Recently I heard of a commercial EMI Filter company > that says the enclosure > is required and that the encapsulant is a > requirement. I disagree. > > -doug > > ======================================= > Douglas E. Powell > Regulatory Compliance Engineer > Advanced Energy Industries, Inc. > 1625 Sharp Point Dr. > Fort Collins, Colorado 80525 USA > m/s: 2018 > --------------------------------------- > 970-407-6410 (phone) > 970-407-5410 (e-fax) > 800-446-9167 (toll-free) > mailto:[email protected] > http://www.advanced-energy.com > ======================================= > > > > > > > > > Hello group, > > > > > > For years I have used off-the-shelf and custom > EMI filters > > with a fully > > > enclosed metal canister. Why is this enclosure > required? Are there > > > specific provisions in the standards? My idea > is to build > > up the filter > > > circuit on a printed circuit board and make it > an integral > > part of the > > > power supply. > > > > > > I am currently looking at EN133200 which has > certain seal > > tests but after > > > reviewing these, they all appear to be related > to climatic or > > environmental > > > conditions. If the product passes these tests > without the > > enclosure it > > > would seem that the product has passed, period. > > > > > > Alternatively I have considered removing the > nomenclature > > "EMI filter" and > > > simply call it an input module, then evaluate it > as a part > > of the overall > > > system. If it passes the EMC and Product Safety > > > requirements, can I call > > > the job complete? > > > > > > Any thoughts? > > > > > > ======================================= > > > Douglas E. Powell > > > Regulatory Compliance Engineer > > > Advanced Energy Industries, Inc. > > > 1625 Sharp Point Dr. > > > Fort Collins, Colorado 80525 USA > > > m/s: 2018 > > > --------------------------------------- > > > 970-407-6410 (phone) > > > 970-407-5410 (e-fax) > > > 800-446-9167 (toll-free) > > > mailto:[email protected] > <mailto:[email protected]> > > > http://www.advanced-energy.com > <http://www.advanced-energy.com> > > > ======================================= > > > > > > --------- > > > This message is coming from the emc-pstc > discussion list. > > > To cancel your subscription, send mail to > [email protected] > > > with the single line: "unsubscribe emc-pstc" > (without the > > > quotes). For help, send mail to > [email protected], > > > [email protected], [email protected], or > > > [email protected] (the list > administrators). > > > > > > > > > > > > > > > > --------- > > This message is coming from the emc-pstc > discussion list. > > To cancel your subscription, send mail to > [email protected] > > with the single line: "unsubscribe emc-pstc" > (without the > > quotes). For help, send mail to > [email protected], > > [email protected], [email protected], or > > [email protected] (the list > administrators). > > > > > > --------- > This message is coming from the emc-pstc discussion > list. > To cancel your subscription, send mail to > [email protected] > with the single line: "unsubscribe emc-pstc" > (without the > quotes). For help, send mail to [email protected], > [email protected], [email protected], or > [email protected] (the list > administrators). > > > ===== Frank West Senior Engineer TUV Rheinland of North America NW/Portland OR Office __________________________________________________ Do You Yahoo!? Thousands of Stores. Millions of Products. All in one place. Yahoo! Shopping: http://shopping.yahoo.com --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
