Answer by
SalimuddinSultan (133)
In a 480 volt three phase system 277 volts is the star point voltage. It can be used for a 277 voltage supply unless the ballast for this type of lighting is multi tapped. A multi tapped ballast on the other hand can be connected to the following voltages, 120, 208, 240, 277, 347, 480 and 600 volts.