Hi,
Does anyone know the reference section in CSA Z462-21 to perform an arc flash analysis on less than 240V systems, I heard this is an update in 2021 edition but was not able to find this reference yet.

Please advise! Thanks

Hi Hayzed

I am part of the technical committee of CSA Z462. We don't specify in the standard anything that directly references voltage systems of 240V or less and conducting an arc flash Incident Energy Analysis. You perhaps may be thinking of back in the 2008 edition, and as also in NFPA 70E where there was a clause that stipulated if the voltage system was 240V or less and fed from one XFMR and the XFMR was less than 125 KVA, one did not have to perform an incident energy analysis. This was of course based on the 2002 edition of IEEE 1584, hence since then there is a later version of IEEE 1584, 2021, in which case there could be issues at 208 3 phase pending on the electrode configuration, the transformer KVA, and impedance this relates to the fault current that the transformer could deliver in the event of a fault condition.

Sustainable arcs are possible but less likely in three-phase systems operating at 240V nominal or less with an available short-circuit current of less than 2000A. This short-circuit current can be delivered by a 30KVA or 45 KVA transformer depending on the transformer’s impedance in %Z

Further, you may want to reference Table V.1 on pages 206- 208 of the 2021 edition

Check-in with Jim and perhaps others on the Forum who are directly involved with the writing of IEEE 1584

I hope that this is of some help

Just clarifying IEEE 1584, 2018 Edition only applies to 208VAC three phase and DOES NOT apply to 240VAC single phase electrical equipment.

Table V.1 in CSA Z462 lists 240VAC single phase but no substantiation was offered (science) that a 240VAC single phase abnormal arcing fault can be sustained.

No trainer or engineering consultant should be advising that arc flash PPE is required for a 120/240VAC panelboard.

Just clarifying IEEE 1584, 2018 Edition only applies to 208VAC three phase and DOES NOT apply to 240VAC single phase electrical equipment.

Table V.1 in CSA Z462 lists 240VAC single phase but no substantiation was offered (science) that a 240VAC single phase abnormal arcing fault can be sustained.

No trainer or engineering consultant should be advising that arc flash PPE is required for a 120/240VAC panelboard.