Which brings up the question about whether central office DC supplies which in some countries or circumstances run up to 70 volts should be considered SELV circuits.
We do not treat the central office supplies as SELV at Motorola. Isolation is provided in switching supplies as with ac mains circuits. Bob "Egon H. Varju" wrote: > Greetings, > > Please note that IEC 950 and all its clones, specifies in Clause 2.3.8, > last dashed paragraph: > > --SELV CIRCUITS shall not use connectors compatible with those specified in > IEC 83 or IEC > 320. > > Very straightforward requirement. It doesn't mention or imply any > exclusions, so this applies to all SELV circuits. > > Egon :-) > > At 10:02 AM 02/11/1998 -0500, you wrote: > >Greetings! > > > >I used to work for Lucent Power Systems which is a MAJOR supplier of > >DC-powering equipment for telecom systems. We used IEC-320 connectors > >in some of our products in non-AC roles. For instance: we used them as > >input connectors to rack-mounted DC-to-DC converters (input: 48Vdc; > >output: 24Vdc) where the IEC-320 inlet on the converter mated to > >shelf-mounted mating connector. Because the product is used in a > >limited-access, trained installation personnel environment, UL accepted > >this application. VDE also accepted this with the caveat that this > >system be inside of a cabinet with doors. > > > >Admittedly, this is a fairly narrow application, but it does demonstrate > >some flexibility in the use of these connectors which is acceptable to > >the regulatory agencies. > > > >-Jeff Haney > >Alcatel > > __________________________________________________________ > > Egon H. Varju, P.Eng. > CSA Pacific Region > Tel: 1-604-244-6640 HAVE MODEM - WILL TRAVEL > Fax: 1-604-244-6600 > E-mail: [email protected] > [email protected] > [email protected] > __________________________________________________________ > > --------- > 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).
