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
        djumbdenst...@tycoint.com <mailto:djumbdenst...@tycoint.com> 

        

        

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This message is from the IEEE Product Safety Engineering Society emc-pstc
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All emc-pstc postings are archived and searchable on the web at
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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:
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