What are the options for marking limited power outputs, e.g., PoE ports, per the NEC Section 725.121(C)?
More specifically you asked: When are PoE ports required to be marked with the output voltage and the output current according to requirements in Section 725.121 of the 2017 NFPA 70 (NEC) and CSA / UL 62368-1 Ed 3 Annex DVA (Q)? For some products, there is not enough space next to the POE port of the equipment to mark the voltage and current, can we use the one of following ways instead of marked on equipment: 1-Marked the output on manual. 2-Add a note on test report such as: the POE output can't connected to building wiring. 3-Other ways.
In response, as the complete answer to this question will depend significantly on the specific construction under consideration for application of NEC Section 725.121(C) and Annex DVA (Q), you are encouraged to contact UL for an in-depth consultation, either via your local account executive or via https://62368-ul-solutions.com/contact-ul.html .
However, in the meantime, below are a few considerations.
-NEC 725.121(C) allows for a single marking to cover multiple ports, and it does not indicate exactly where the label must be placed. Therefore, there may be additional ability to meet the requirement than you indicated. Also, Annex DVA (Annex Q) currently allows for such a label to be supplied with the equipment, and to be applied at the installation, so this may be another option.
-There is no stipulation in the NEC that the required marking can be in a manual, which is reasonable since the information in the marking will be used by electricians wiring per the NEC and Authorities Having Jurisdiction (AHJ) inspecting the equipment for compliance with the NEC. The needed information located in a manual may not be helpful.
-building wiring is a term used in 62368-1 and is not specifically used in NEC 725. However, if the specific equipment with PoE ports will use a wiring method (e.g., Listed CL2 cable) covered by Article 725 (or 840), it would be considered building wire per UL 62368-1. Most PoE ports will use Article 725 wiring methods, so the proposal to add into the test report that the PoE can’t be connected to building wiring would not be reasonable solution in most cases.
We encourage you to consult our NFPA 70-2017 and NFPA 70-2020 UL Impact Analyses for additional information - both are available in the 62368 UL Toolkit.
Please also review the content of the current Annex DVA (Annex Q) National Difference for 725.121(C).
“If applicable based on 725.121(C) being required for the equipment, limited power sources for listed audio/video, information, and communications technology (equipment) covered in 725.121(A)(4) shall have a label indicating the maximum voltage and maximum current, or the maximum voltage and nominal current output for each connection point. Where multiple connection points have the same rating, a single label may be used. The marking shall not be required for power sources providing 0,3 amperes nominal current or less per conductor. The marking shall be provided on the equipment, permanently, or shall be provided with the equipment for permanent application and ready inspection after installation. Other options for the manufacturer to supply this information to the installer and fulfill the provisions of the NEC and CE Code, Part I, may be considered at the discretion of the manufacturer.”