210.6 Branch-Circuit Voltage Limitations. The nominal
voltage of branch circuits shall not exceed the values permitted
by 210.6(A) through 210.6(B).
(A) Voltage Limitations. In dwelling units the voltage shall not exceed 120 volts, nominal, between
conductors that supply the terminals of the following:
(1) Luminaires (lighting fixtures)
(2) Cord-and-plug-connected loads 1440 volt-amperes,
nominal, or less or less than 1⁄4 hp
(B) 120 Volts Between Conductors. Circuits not exceeding
120 volts, nominal, between conductors shall be permitted
to supply the following:
(1) The terminals of lampholders applied within their voltage
ratings
(2) Auxiliary equipment of electric-discharge lamps
(3) Cord-and-plug-connected or permanently connected
utilization equipment
