480 Wiring Diagram - Is 480V Always 3 Phase?

In North America, 240–120 volts can either be a single-phase or a three-phase delta connected service. Delta, 3-phase services were once the most common type of 3-phase service, but now, most 3-phase services in the U.S., are either 208 - 120 volt, or 480 - 277 volt wye connected.

Is 480 a line or V line?

In a 3-Phase Supply system, the lower voltage (typically 277V or 347V) will be the 'Line to Neutral Voltage' which is the measured voltage between one of the three lines and the neutral. The higher voltage (typically 480V or 600V) will be the 'Line to Line Voltage'.