Dear y'all (strange, I do not remember meeting any rednecks in Israel) Read and heed the advice of Mr Eckert - his MS job has probably resulted in much experience with the physical layer of TCP/IP. To expand on his comments - read article 725 before you decide to use Class 2 wiring materials.
A good reference for these questions is probably Peter Tarver - perhaps he will respond. 1. Cat 5e cable is defined by TIA-568-B. The connector is defined by TIA-1096-A. The UL-recognized material that I have used is rated 120V WV, 1.5A, and 1500V di-electric withstand - so the wiring stuff is available. Unfortunately, I have not found any suitably-rated plastic patch panels - so use metal construction to mount the stuff. 2. Depends if exits building, max overload current and VA available, reference of a local protective earth, and the ratings and C of A for the power source. 3. Do not understand the need for a "new definition", see 2.6 and 6.2 of 60950-1 and section 6 of 60950-21. SELV and TNV-1 do not meet all requirements for use of Class 2 wiring materials. In addition to electrical code issues, you will find that the RJ connectors are not suitable for construction that is exposed to home-user/installer. Brian From: [email protected] [mailto:[email protected]]On Behalf Of Ted Eckert Sent: Wednesday, May 26, 2010 6:11 AM To: Ilan Cohen; [email protected] Subject: RE: PoE which is not power limited. Hello Ilan, One problem you will run into is in the United States and Canada. The power levels transmitted mean that these are no longer Class 2 power limited circuits under the National Electrical Code (NEC) or Canadian Electrical Code. This means that the cables can't be run through buildings the way you can normally route Cat5. In commercial installations, the wiring may need to be in conduit. The NEC will likely put severe restrictions on the routing of PoH. I would be interested in knowing if the developers have come up with ways around this problem. Regards, Ted Eckert Compliance Engineer Microsoft Corporation [email protected] From: Ilan Cohen [mailto:[email protected]] Sent: Wednesday, May 26, 2010 4:50 AM To: [email protected] Subject: PoE which is not power limited. Hi ya all There is an exciting new technology emerging called PoH (power over HD Base T) intended to deliver 200W (DC- up to 60V) using Cat5, Cat6 cables. One of the main applications will be powering TV screens. Now the screens can be very flat and powered by only one Cat5 cable which caries power data to the screen. A big challenge here is that we are not in power limited circuit anymore, as it is with PoE circuits. Your opinion about the following will be appreciated: 1) Cat5 cables - are they allowed to carry 1 A ? (they are typically 24AWG and rated 0.577A) 2) Are you/we going to require same insulation requirements as in PoE ? (1500V) 3) Are we talking SELV, TNV1 or we have a new definition we need to look for compliance? (such as taking 60950-21 into consideration ) Ilan Cohen, David Heald <[email protected]> - 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 <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
