277 Volts is the input power of choice for most industrial and commercial applications. High voltage lighting is better from an efficiency standpoint. Higher voltage means less current, which means less power loss from resistance as stated in  Ohm’s and Joule’s laws.

Ohm’s law:  Voltage = Current*Resistance

Joule’s law: Power = Voltage*Current

High voltage lighting means you can put more lighting fixtures on a given circuit because voltage drop is less of a concern. This means these lights are ideal for areas with a lot of lighting fixtures close together: think warehouses, offices, restaurants, hotels, schools, and even hospitals.

Most industrial facilities get their power in a 480/277 volt 3 phase 4 wire system, because 277 is the phase-to-neutral voltage for 480’s phase-to-phase. The 480 volt wiring is generally used to power large industrial equipment, and the 277 volt wiring powers industrial scale lighting. These two voltages tend to go together because you do not need a transformer to use the 277 voltage, which cuts down on energy and construction costs.

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