I believe that DT is the only carrier that uses -60Vdc CO's, but I think that it is only present in their older CO's.
It's not that hard to meet the requirements though - just maintain 1mm (40th) creepage & clearance between TNV-2 and SELV, GND, etc (up to your DC/DC's/opto-isolators/bridging caps) and make sure any bridging capacitors are physically large enough to have 1mm between the pads (Y rating is not required but anything smaller than a 1206 SMT cap is too small to maintain spacings). Voltage rating on the caps is important too, I guess - pick according to proper NEBS reliability derating. -And you may have to ensure that your DC/DC's are rated properly. Best Regards, Dave Heald ----- Original Message ----- From: "Joe Finlayson" <[email protected]> To: "'EMC PSTC'" <[email protected]>; "'NEBS Newsgroup'" <[email protected]> Sent: Thursday, April 03, 2003 2:39 PM Subject: C.O. Battery Voltages - EVERYWHERE >I'm interested in obtaining information on the percentage of C.O.'s >worldwide that are utilizing -60VDC as their battery voltage. It is my >understanding that a majority use -48VDC although some still use -60VDC. >Any and all information/references would be helpful. If there are >references that are country specific or carrier specific, that would be >valuable information as well. Any charts/spreadsheets out there similar >to the mains supply charts I've seen would be excellent. > >Thx, > > >Joe > >************************************* >Joe Finlayson >Manager, Compliance Engineering >Telica, Inc. >734 Forest Street, Bldg. G, Suite 100 >Marlboro, MA 01752 >Tel: (508) 804-8212 >Fax: (508) 480-0922 >Email: [email protected] > 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: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
