"2.2.2 Voltages under normal conditions In a single SELV CIRCUIT or in interconnected SELV CIRCUITS, the voltage between any two conductors of the SELV CIRCUIT or CIRCUITS, and between any one such conductor and earth (see 1.4.9), shall not exceed 42,4 V peak, or 60 V d.c., under normal operating conditions. NOTE 1 A circuit that meets the above requirements, but that is subject to overvoltages from a TELECOMMUNICATION NETWORK or a CABLE DISTRIBUTION SYSTEM, is a TNV-1 CIRCUIT. NOTE 2 For normal conditions, the SELV CIRCUIT voltage limit is the same for an ELV CIRCUIT; an SELV CIRCUIT may be regarded as an ELV CIRCUIT with additional protection under fault conditions."
It seems Note 1 suggests that Ethernet as Telecommunication Network is a TNV-1 circuit (see also Table 1A).. For more details check also https://ewh.ieee.org/r6/scv/pses/ieee_scv_pses_jun07.pdf. Lubo On Mon, Jul 3, 2017 at 8:11 PM, Joe Randolph <j...@randolph-telecom.com> wrote: > Hi Curtis: > > > > In general, Ethernet cables are classified as SELV under EN60950. Is the > barrier you are concerned about the one between the Ethernet cable and > another SELV circuit, or is it a different barrier between hazardous > circuits and the Ethernet cable? > > > > For the barrier between the Ethernet cable and SELV, there is no > regulatory requirement for creepage and clearance because both sides of the > barrier are classified as SELV. However, for compliance with IEEE 802.3, > there is a 1500 VRMS dielectric test (among other options) for this > barrier. IEEE 802.3 is an industry standard rather than a regulatory > standard, so compliance with IEEE 802.3 is voluntary. > > > > Having said all of the above, there has been much consternation among > telecom compliance engineers regarding whether Ethernet cables that are > routed outside the building should be classified as TNV. As a member of > the Telecom TAC for the IEEE PSES, I am very familiar with these > discussions, but I won’t try to summarize the different views here. > Suffice it to say that the topic is being hotly debated. > > > > In the meantime, EN60950 does not presently require creepage and clearance > distances for the barrier between an Ethernet cable and the corresponding > Ethernet PHY chip on the other side of the isolation transformer. > > > > I can provide more details on this if you are interested. > > > > > > Joe Randolph > > Telecom Design Consultant > > Randolph Telecom, Inc. > > 781-721-2848 <(781)%20721-2848> (USA) > > j...@randolph-telecom.com > > http://www.randolph-telecom.com > > > > *From:* Curtis McNamara [mailto:mcnam...@umn.edu] > *Sent:* Monday, July 03, 2017 6:11 PM > *To:* EMC-PSTC@LISTSERV.IEEE.ORG > *Subject:* [PSES] Ethernet spacing and product insulation > > > > I am doing a pre-check on a product with Power Over Ethernet. The PCB > doesn't appear to have sufficient spacing (creepage and clearance) between > the incoming TX/RX circuitry and the isolated circuitry on the product side > of the transformer. > > However, it comes with an integral plastic mounting plate and instructions > to mount it into an opening in a wall (similar to an electrical outlet box > cover). The spacing between the circuitry and the plastic mounting plate > (and the thickness of the plastic mounting plate) provide sufficient > separation from either side of the Ethernet transformer. There are no user > accessible openings. > > Could this pass approval (for example EN62368 or EN60950) with > restrictions that it be properly mounted? The Ethernet is building only. > > Thanks in advance, this list is a great resource and much appreciated. > > Curt > > - > ---------------------------------------------------------------- > > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to < > emc-p...@ieee.org> > > All emc-pstc postings are archived and searchable on the web at: > http://www.ieee-pses.org/emc-pstc.html > > Attachments are not permitted but the IEEE PSES Online Communities site at > http://product-compliance.oc.ieee.org/ can be used for graphics (in > well-used formats), large files, etc. > > Website: http://www.ieee-pses.org/ > Instructions: http://www.ieee-pses.org/list.html (including how to > unsubscribe) <http://www.ieee-pses.org/list.html> > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > Scott Douglas <sdoug...@ieee.org> > Mike Cantwell <mcantw...@ieee.org> > > For policy questions, send mail to: > Jim Bacher <j.bac...@ieee.org> > David Heald <dhe...@gmail.com> > - > ---------------------------------------------------------------- > > This message is from the IEEE Product Safety Engineering Society emc-pstc > discussion list. To post a message to the list, send your e-mail to < > emc-p...@ieee.org> > > All emc-pstc postings are archived and searchable on the web at: > http://www.ieee-pses.org/emc-pstc.html > > Attachments are not permitted but the IEEE PSES Online Communities site at > http://product-compliance.oc.ieee.org/ can be used for graphics (in > well-used formats), large files, etc. > > Website: http://www.ieee-pses.org/ > Instructions: http://www.ieee-pses.org/list.html (including how to > unsubscribe) <http://www.ieee-pses.org/list.html> > List rules: http://www.ieee-pses.org/listrules.html > > For help, send mail to the list administrators: > Scott Douglas <sdoug...@ieee.org> > Mike Cantwell <mcantw...@ieee.org> > > For policy questions, send mail to: > Jim Bacher <j.bac...@ieee.org> > David Heald <dhe...@gmail.com> > -- Lubo Cekov - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
