When will IEC 62368-3:2017 be required to be used with IEC 62368-1?
In December 2017, IEC TC108 published IEC 62368-3, Audio/video, information and communication technology equipment – Part 3: Safety aspects for DC power transfer through communication cables and ports.
IEC 62368-3 contains hazard-based content (in its Clause 6) that reflects the requirements previously contained in IEC 60950-21 for remote power feeding telecommunication (RFT) circuits, along with new requirements (in its Clause 5) for DC power transfer at ES1 and ES1 levels, such as associated with USB and PoE.
Per its Foreword,
“This International Standard is to be used in conjunction with IEC 62368-1:2014. It has the status of a group safety publication in accordance with IEC Guide 104. The subclauses of IEC 62368-1 apply as far as reasonable. Where safety aspects are similar to those of IEC 62368-1, the relevant clause or subclause of IEC 62368-1 is given for reference in a note in the relevant subclause. Where a requirement in IEC 62368-3 refers to a requirement or criterion of IEC 62368-1, a specific reference to IEC 62368-1 is made.”
Therefore, when AV/ICT equipment has circuits covered by IEC 62368-3, it is the intent of IEC TC108 that both IEC 62368-1 and IEC 62368-3 apply (similar to how IEC 60950-1 and IEC 60950-22 are applied to Outdoor ITE).
The application of IEC 62368-3’s Clause 6 for ICT equipment utilizing RFT circuits will be relatively straightforward, similar in application to IEC 60950-21, Remote Power Feeding. However, only limited constructions of ICT equipment utilize RFT circuits, so Clause 6 will be used infrequently.
Application of Clause 5 will be much more frequent since dc power transfer via USB, PoE and related protocols are very common in many forms of AV & ICT equipment. Therefore, it will have widespread applicability.
Nevertheless, there a few key hurdles associated with the application of IEC 62368-3. These are more covered in some detail in our pending 62368-3 Backgrounder paper.
For example, specifically for Clause 5, much of the clause relies on principles, terminology and limits in industry standards, like USB 3.0 and IEEE 1394. However, the terminology used in IEC 62368-3 does not always correlate clearly with these industry standards, so there remains some confusion cross-referencing and correlating requirements.
Furthermore, the adoption of both IEC 62368-1 Ed. No. 3 and 62368-3 likely won’t be concluded in regions/countries like Europe, Canada and the U.S. until deep into 2019 at the earliest, and it’s unknown at this time will the content of 62368-3 be adopted in national standards without change.
Considering the above, it is unlikely IEC 62368-3 will be required for AV/ICT equipment and components until sometime deep into year 2019.