430 Motor and 440 AC Load Calculations

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DW98

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Question about how to include motor and hvac calcs in the panelboard feeder schedules. I'm confused about whether you add 25% for the largest load of a piece of equipment to the fla of the other loads, and then add all the units up. or if you consider all the units together and add only 25% to the largest load.

fla = full load amps, mca = minimum circuit amps.

Example 1: ten rooftop 208V 3PH gas heat/electric cooling rooftop units, fla/mca = 80/100A. Do you use mca*volt*sqrt(3) = 100A*208*1.73 = 36 kva for all units for a total of 360 kva. Or do you only include mca*volt*sqrt(3) for one unit, and fla*volt*sqrt(3) = 28.8 kva for the others for a total of 36 + 8*28.8266.3 kva?

Example 2: Motors: i think i'm clear on motors. Add up all motor fla, and add 25% to largest motor fla

I've created linked excel load spreadsheets and am trying to nail down the formulas
 
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