The ADSL modem connects directly to the phone line. The filters go on the rest of your phones in the house to block any interference in the voice band. The ones I have seen would be considered TNV-3 on both sides. But they would at least need to be TNV-2 on the phone side because you would still need to pass the ring signals.
I have done safety and telecom approvals on a couple of ADSL modems and the port was treated as TNV-3. The SDSL and IDSL modems I have done approvals on, the port was treated as TNV-1. I just got ADSL service for my house. The modem and all the filters were UL listed as well as Part 68 approved. FWIW, if you had a splitter that had a TNV-3 barrier in it the other side would be either SELV or TNV-2 not TNV-1. However, the splitters I have seen have no barrier and are TNV-3 on both sides. Dave Clement Motorola Inc. Test Lab Services Homologation Engineering 20 Cabot Blvd. Mansfield, MA 02048 P:508-851-8259 F:508-851-8512 C:508-725-9689 mailto:[email protected] http://www.motorola.com/globalcompliance/ -----Original Message----- From: Peter Merguerian [mailto:[email protected]] Sent: Wednesday, September 18, 2002 9:24 AM To: 'Rob Keller'; [email protected] Subject: RE: DSL Modems Rob Hi! I assume that the "ADSL" modem is connected to the phone line through an external splitter. If you find an approved splitter having the required TNV-3 to TNV-1 insulation, and you specify the specific splitter in your manual, I gather that your interface can be TNV-1. If no such splitter is specified, then the interface should be classified TNV-3. Now a question to the group - is anyone familiar with external Listed/Certified splitters that have the TNV-3 - TNV-1 insulation? This e-mail message may contain privileged or confidential information. If you are not the intended recipient, you may not disclose, use, disseminate, distribute, copy or rely upon this message or attachment in any way. If you received this e-mail message in error, please return by forwarding the message and its attachments to the sender. PETER S. MERGUERIAN Technical Director I.T.L. (Product Testing) Ltd. 26 Hacharoshet St., POB 211 Or Yehuda 60251, Israel Tel: + 972-(0)3-5339022 Fax: + 972-(0)3-5339019 Mobile: + 972-(0)54-838175 http://www.itl.co.il http://www.i-spec.com -----Original Message----- From: Rob Keller [mailto:[email protected]] Sent: Tuesday, September 17, 2002 10:38 PM To: [email protected] Subject: DSL Modems Greetings all, Question regarding the classification of DSL modems. DSL modems connect to the standard telecom network yet they do not require a ring signal or go on/off hook, therefore the classification would be TNV-1. Yet there are ring signals still present on the telecom lines for the the other equipment. So, because of the ring signals, which would exceed the limits of SELV, connecting to the input the modem, should the classification be TNV-3. Any insight would be greatly appreciated. Rob Keller Product Safety Engineer Communication Certification Laboratory [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] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" ------------------------------------------- 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] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list" ------------------------------------------- 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] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
