Which voltage is more efficient?

We get asked this a lot…. which voltage is more efficient, 460V, 3ph, 60hz or 230V,
3 ph, 60hz? The answer is neither…..they are the same.
People often see that the amp rating for the 460V motors is ½ that of the 230V motors, but remember,
the voltage is double.

True Power (KW) = 1.732 * Voltage * Current * COS (phase angle) / 1000 (assume phase angle = 0.9)
KW(460V) = 1.732 * 460V * 56A * COS (0.9) / 1000 = 44.61 KW
KW(230V = 1.732 * 230V * 112A * COS (0.9)/ 1000 = 44.61 KW

The power consumption for the 460V is the same as the 230V.

The benefit of the 460V power is the smaller components. Smaller main power disconnect, smaller wire
feeding the disconnect and wire to the machine, as well as a smaller compressor contactor.