Hi Dave,
According to Annex B of ETSI document EG 201212 "Electrical safety; Classification of interfaces for equipment to be connected to telecommunication networks": "48 Volt" Station Battery is to be considered as SELV where Vmax =< 57Vdc. "60 Volt" Station Battery is to be considered as TNV-2 where Vmax =< 75Vdc. As Ed described the input as going up to 72Vdc, then, IMHO, this circuit should be classified as TNV-2 with the above reference and with the TNV-2 circuit definition found in IEC/EN/UL60950. Also see clause 5.3 of EG 201212 for user information recommendations. The above assumes that Ed's product connects to a telecommunication network. Please note that as the EG of EG 201212 refers to "ETSI Guide" (see the foreward), its hardly a regulatory requirement, however, it is a useful document that provides guidance for the classification of most TNV type circuits. And, it can be downloaded for free from the ETSI site. I hope this helps clarify this issue. Comments? Best regards, Ron Pickard [email protected] [email protected] Sent by: To: [email protected] owner-emc-pstc@majordom cc: [email protected], [email protected] o.ieee.org Subject: Re: TNV-2 to Earth requirement 01/17/02 02:33 PM Please respond to daveheald Does your equipment plug into a primary (AC) circuit? Any TNV circuit is considered a secondary circuit and if any and all power is derived from the TNV network, the notes you referenced would not apply as a primary circuit is not present. Best Regards, Dave Heald Ed Eszlari wrote: > > All, > > I have a DC to DC "filter" which is rated 32 - 72 VDC input and output > which I am considering to be TNV-2 according to EN60950/IEC60950 2nd > edition. > > This filter has a metal chassis which is earthed, and it will be > installed in a service access area only by qualified service > personnel. It is not permanently connected or pluggable type B, and > does not have a provision for a permanently connected earthing > conductor. With all this considered, it seems that Norway and Sweden > are the only Countries that require Supplemental insulation for a > primary circuit between this TNV-2 circuit and earth. > Is there any way around this requirement due to this filter operating > at 72VDC and not being directly connected to mains? > > Any help would be appreciated. > > Ed > > ---------------------------------------------------------------------- > MSN Photos is the easiest way to share and print your photos: Click > Here > ------------------------------------------- This message is from the > IEEE EMC Society Product Safety Technical Committee emc-pstc > discussion list. Visit our web site at: > http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, > send mail to: [email protected] with the single line: unsubscribe > emc-pstc For help, send mail to the list administrators: Michael > Garretson: [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: No longer online until our new server is > brought online and the old messages are imported into the new server. ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: [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: No longer online until our new server is brought online and the old messages are imported into the new server. ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: [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: No longer online until our new server is brought online and the old messages are imported into the new server.
