A primary question in the US is: Does the circuit qualify as a Class 2 (or Class 3) circuit according to the National Electrical Code? (ref: NFPA 70 clause 725.121) If it fails to qualify, then wiring requirements become quite stringent. There are seven possibilities: a listed Class 2 transformer, a listed Class 2 power supply, listed equipment marked to identify the Class 2 output, thermocouples, limited power circuits of listed equipment meeting chapter 9 requirements, listed information technology equipment limited power circuits, or batteries with capacity at or below No 6 carbon zinc cells.
To my mind, in this situation, that means the circuit must be both "listed" and a "limited power circuit". The decision of determining compliance with the criteria for a limited power circuit is, to a small extent, left to the listing agency. However, it seems the limited power circuit designation is an important part of code requirements. Providing a circuit which cannot be considered a Class 2 or Class 3 circuit and must use Class 1 wiring methods will place an immense installation burden on the user. Bob Johnson ITE Safety <http://www.itesafety.com> Umbdenstock, Don wrote: Dear Colleagues, I have perused the IEEE 802.3af explanation on various web sites and examined supplier specs. I came to the conclusion that the injector should be LPS certified and marked as such. However, most of the injectors I have found by web search do not indicate LPS. Does anyone believe that a PoE injector does not require LPS certification? If so, why not? Regards, Don Umbdenstock Manager Compliance Engineering Tyco Safety Products / Sensormatic 6600 Congress Avenue Boca Raton, FL 33487 USA Phone: 561.912.6440 [email protected] <mailto:[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]> - 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]>
