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Repeat Example 1.2 using Lee’s equations.

The incident energy is given by Equation (1.7). Substituting the values:

This gives 126.6 cal/cm², and from Equation (1.6), distance in feet for a curable burn is 30.82 ft. There is a vast difference in these calculations: 11.6 cal/cm² with IEEE method and 126.6 cal/cm² with Lee’s method; his equations do not consider system grounding, and do not calculate arc flash currents.