Such protection shall be provided by an overcurrent device
in series with each ungrounded service
conductor that has a rating or setting not higher than the ampacity
of the conductor. A set of fuses shall be considered all the fuses required to protect all the ungrounded
conductors of a circuit. Single-pole circuit breakers
, grouped in accordance with 230.71(B)
, shall be considered as one protective device
Exception No. 1: For motor-starting currents, ratings that comply with 430.52, 430.62, and 430.63 shall be permitted.
Exception No. 2: Fuses and circuit breakers with a rating or setting that complies with 240.4(B) or (C) and 240.6 shall be permitted.
Exception No. 3: Two to six circuit breakers or sets of fuses shall be permitted as the overcurrent device to provide the overload protection. The sum of the ratings of the circuit breakers or fuses shall be permitted to exceed the ampacity of the service conductors, provided the calculated load does not exceed the ampacity of the service conductors.
Exception No. 4: Overload protection for fire pump supply conductors shall comply with 695.4(B)(2)(a).
Exception No. 5: Overload protection for 120/240-volt, 3-wire, single-phase dwelling services shall be permitted in accordance with the requirements of 310.12.