Load Calculations

[jared albrecht]

If I have a peak demand for an existing panel A, say 33kVA, and the owner wants duplicate the same loads and equipment and add to panel A (effectively there will be 2 off every piece of equipment and device when added), what keeps us from just using the, 33x1.25=41.2, 41.2kVA and multiplying by 2 for the total load?

 

[Julius Right]

If you are speaking about the supplying feeder then, according to NEC art. 215.2 Minimum Rating and Size.(A) Feeders Not More Than 600 Volts. a):
Where a feeder supplies continuous loads or any combination of continuous and noncontinuous loads, minimum feeder conductor size shall have an allowable ampacity the not less than the noncontinuous load plus 125 percent of the continuous load.
If 33 kVA total it is only continuous load then you have to multiply by 2*1.25 in order to find the feeder required ampacity.