<[email protected]>, Ehler, Kyle <[email protected]> inimitably wrote: > > Greetings, > > I have a new product that includes an off the shelf UPS that is rated for > 230V ac operation and has an internal single pole circuit breaker on the > mains inlet. We want to target this product world-wide. The UPS > presently > is CB and certified to EN60950 european only. For North America we want > it > to have UL1950, and to obtain this, UL is demanding the breaker be double > pole. > > Many of our existing products (including this new product) employ SMPS > type > power supplies that are fused on the line side only, yet they are > certified > to EN60950, UL1950 and CB. How can these products be acceptable yet >another > cannot? > > Am I missing something? > I'm confused. (no pun intended :) > Yes, you would be. It's a fudge. The standard actually calls for double- pole (in Table 1, cases B and C, in EN60950:1992 with all amendments), but rather obscurely. Case B ought to apply in Europe, because the mains plugs used in Germany, Netherlands, Austria and some other countries are 3-contact but *reversible*, so a single fuse or switch may actually be in the neutral. However, you are NOT SUPPOSED TO NOTICE THAT! -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk This message and its contents are not confidential, privileged or protected by law. Access is only authorised by the intended recipient - this means YOU! The contents may be disclosed to, or used by, anyone and stored or copied in any medium. If you are not the intended recipient, please advise the sender yesterday at the latest.
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