I just arrived in Geneva, Switzerland for IEC meetings which prompted this week's question. It is about IEC vs. ANSI/IEEE Standards for short circuit current calculations.

Depending on which method is used, the results can vary a bit which may also affect the calculated incident energy.

Here is this week's question:

Which short circuit calculation method do you use?

ANSI/IEEE
IEC
Both
Other (please describe)
I Don't Perform Studies

I prefer comprehensive method factoring in all the equipment active, reactive impedance and contribution to fault current. Also, I find it important to know the range of available fault current (min - max) and take into account arc duration so I can identify worst case arc flash scenario. Incident energy alone is meaningless unless you know how fast that energy has been delivered. Jim, let me know please if I can be of any help elaborating on or escalating this issue to decision making authorities.