Hi, Joe. On 27 Mar 2009 at 0:59, Joe Randolph wrote: > > On 3/26/2009, Peter Tarver wrote: > > > What if the power supply is Class 2 Equipment? > > Hi Pete: > > A Class 2 supply is the most common type of supply that I > have seen for POE injection. And yes, the output should be > isolated from earth ground to comply with IEEE 802.3af. > > Personally, I do not see any safety compliance problems with > this construction when used as intended (inside lines).
I was specifically responding to [email protected] statement: > 2) The power supply in the sourcing equipment are > isolated per IEEE 802.3 (1500Vrms). in the context of Class 2 Equipment type power supplies needing (typically) 3 kV isolation to the AC Mains. This is indeed safe and presents no issues. I simply wanted to make certain that no one mistakenly assumed 1.5 kV isolation was all that might ever be required. Probably a knee-jerk reaction on my part, since [email protected] probably already knows this. Keep in mind, also, that there're differences between a Class 2 power supply, in the NEC sense, and a Class 2 Equipment power supply, in the 60950-1 sense. Between your wording and Robert Johnson's post, I'm not sure which you meant, though that doesn't matter much. Peter Tarver [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]>
