JBD wrote:
I have never cared for calculating AFIE at different points within a control cabinet, unless it is very large with multiple doors. In my opinion this is similar to not calculating AFIE at multiple points within a circuit breaker panel or switchboard. There are too many variables to consider as far as the arc propagation...
I agree. Not only that, I don't think you can. At least not accurately. I don't know that IEEE did any of that type of testing and developed the formulas based on that. Most the videos I've seen of their tests basically involved installing a small gauge jumper wire or in a few instances a common tool across phases at the line side and turned it on.
I mentioned in the video that I had asked SKM about using PTW to model the "guts" of a piece of equipment. It was basically power electronics but had terminal blocks, fuse blocks, tap conductors of different gauges, relays etc. similar to a industrial control panel but not exactly. I suspect the answer would be similar if I asked them about modeling the "guts" of a control panel but admittedly I have not tried. Here is the response I got back:
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