SteveA wrote:

1584-2018 will have some pretty major updates to the DC.

No.

As per IEEE 1584 Draft 6 section 4.11: "Arc-flash incident energy calculation for DC systems is not part of this model. However, publication references XXXprovide some guidance for incident energy calculation."

Other than providing references there is nothing in the model discussing DC at all just as 1584-2002 was silent on the subject.

All of the data you mentioned (Paukert, etc.) are all about determining the V-I curve but they don't go to the point of actually calculating incident energy or have anything to do with it. Neal's model as mentioned is just the DC version of Lee (maximum power transfer argument). Ammerman goes further by taking Paukert, Opplander, etc., and using it as a theoretical DC arc model by basically modelling the arcing voltage as nearly constant (slowly increasing) which is what the V-I curves show for a power arc, then using this as the basis for the arc power and assuming perfect heat transfer and no arc "shape". So the basic model is different from the maximum power transfer and it's about 65% of the incident energy predicted by the maximum power transfer model but despite the improvements, it goes nowhere. And this is once again a purely theoretical model, NOT based on measurements.

As to the data, the Paukert and Stokes and Oppelander data is actually very old, not new, and not part of the joint IEEE/NFPA arc flash testing. There is no incident energy calculated. It's just V-I curves. The same data you mentioned and the Etap presentation are right out of the presentations that Ammerman did, as opposed to this paper that deals with the paltry amount of real world data out there and compares it to both the maximum power transfer and the Ammerman models and shows that even at low voltage, they are WAY off. No way you can say much, if anything, about application at >1 kV other than it's all theoretical so we're all guessing.

http://www.battcon.com/PapersFinal2012/ ... 0Flash.pdf