Getting the Amps from Watts, Amps and the voltage of a line What amperage capacity should the supplied wired be rated for a refrigerated fixture which has a 208V power supply and the following loads? * 4 Evaporator fan motor rated at 9W each * 4 Evaporator fan motor rated at 9W each * 6 Florescent lights rated at 40W each * 1 strip Mullion heater rated at 3 A What I tried was: (4*9W) + (4*9W) + (6*40W)+(3A*208V)= 936W Then I divided by 208V to get that to AMPS 936W/208V this answer is 4.5 but the expect answer is 20A Can someone please should how you would calculate this. Thanks for the help!

Your answer is correct given the data we have. The motors will presumably have a higher starting current than running current, so in real life you need to allow for that. 20A is substantially higher than needed, however.