Hello Jim, Thank you very much for your excellent advice. Indeed, I found a similar spec to the one you suggested, namely Bellcore TR 62411, that specifies the same. I was confused since a more recent spec, namely ANSI T1.403-1995 actually forbids the use of DC power: see section 6.5. However, since our products should be compatible with older equipment as well, your advice is excellent.
Thanks again, Dorin JIM WIESE wrote: > > The requirements for a T1 CSU are located in Bellcore TR-TSY-000312 > Issue1, March 1988. Section 2.3 will give you the detailed answer your > looking for, however the short answer is you do need to provide the DC > path. The reason is that midspan repeaters will not function if the > path is broken. This Bellcore document tells you everything you need to > know about "DS1 interface connectors" (Bellcore's name for T1 smart > jacks, T1 CSU's etc) needs to do. > > Jim > > James Wiese > Regulatory Compliance Engineer > ADTRAN, Inc. > 205-963-8431 > 205-963-8250 FAX > [email protected] > > >---------- > >From: Jon D Curtis[SMTP:[email protected]] > >Sent: Thursday, December 18, 1997 9:59 AM > >To: [email protected] > >Subject: BOUNCE [email protected]: Non-member submission from > >[Dorin > >Gheciu <[email protected]>] (fwd) > > > >From: Dorin Gheciu <[email protected]> > >Subject: T1 CSU compliance > > > > Is anyone aware of a need to provide DC continuity > >through T1 CSU's ? > > > >Before 1989, T1 CSU's used to be powered by access > >providers. To accomplish this, the access provider > >would send DC current that would loop back via the > >center taps of the Tx and Rx transformers of the CSU. > > > >Although this requirement has been abolished, I was > >advised by a colleague to still connect together the > >center taps, since some Telco's may expect it, and use > >it for "contact wetting". Unfortunately, it complicates > >the surge protection of the CSU. > > > >Thanks, > >Dorin Gheciu > >Mororola ISG > > > > > > RCIC - http://www.rcic.com > > Regulatory Compliance Information Center > > > > > > > > -- Dorin Gheciu Senior Staff Engineer Motorola ISG Tel:(905)712-7556 Fax:(905)507-7200
