David Law asked the status of IEC 62368. I find the electric strength test (5.4.9, 5.4.10) to be nearly identical to 60950. Voltage limiting devices may be removed during test. I didn’t make this point, but leads are shorted together during
test. The device is then non-operational.
We seem to already require more extensive compliance with 62368 (“applicable sections”) within Clause J.2 (10/100/1000…, fiber, PSE/PD). See below.
We are more specific about isolation with J.1, however J.1 does not reference 62368 (likely why I missed it).
I now wonder if the CRG ( https://www.ieee802.org/3/cr/Comments/D3.0_Unsatisfied.pdf)
should have done more than just rejected the comment. If there really was disagreement, then it should have been made clear what the intended test procedure should have been.
J.1 states that there used to be guidance for a) and b), but also that no technical change is implied by the removal of the reference. This seems to imply that the referenced procedure (implying removal of parts) is still valid.
NOTE 2—IEEE Std 802.3-2018 and previous revisions provided references to various editions of the IEC 60950-1
standard for guidance in performing the isolation test for options a) and b). IEC 60950-1 has been withdrawn.
References to IEC standards are not essential to performing the isolation test specified in J.1. No technical change is
implied by the removal of these references.
Guidance in performing the isolation test for options a) and b) is fully
contained within IEEE Std 802.3-2022.
Since we never say part removal is allowed – then it is not allowed.
Another option (if we don’t believe 802.3 contains the entire procedure) is to reference IEC 62368, but add an exclusion for part removal.
NOTE 2—IEEE Std 802.3-2018 and previous revisions provided references to various editions of the IEC 60950-1
standard for guidance in performing the isolation test for options a) and b). IEC 60950-1 has been withdrawn.
References to IEC standards are not essential to performing the isolation test specified in J.1. No technical change is
implied by the removal of these references.
Guidance in performing the isolation test for options a) and b) is
contained in IEC 62368-1:2018, 5.4.9 and 5.4.10, with the following exception to 5.4.9.1: Components providing a DC path
in parallel with the insulation to be tested, such as discharge resistors for filter capacitors and voltage limiting devices,
may NOT be disconnected.
Probably this means designing MOVs out of the circuits. Test c) would test MOVs with impulses, but then the 500 V dc would be damaging.
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