Part II. Buildings or Other Structures Supplied by a Feeder(s) or Branch Circuit(s)
225.30 Number of Supplies.
A building or other structure that is served by a branch circuit or feeder on the load side of a service disconnecting means shall be supplied by only one feeder or branch circuit unless permitted in 225.30(A) through (E). For the purpose of this section, a multiwire branch circuit shall be considered a single circuit.
Where a branch circuit or feeder originates in these additional buildings or other structures, only one feeder or branch circuit shall be permitted to supply power back to the original building or structure, unless permitted in 225.30(A) through (E).
225.30(A) Special Conditions.
Additional feeders or branch circuits shall be permitted to supply the following:
(1) Fire pumps
(2) Emergency systems
(3) Legally required standby systems
(4)Optional standby systems
(5)Parallel power production systems
(6)Systems designed for connection to multiple sources of supply for the purpose of enhanced reliability
(7)Electric vehicle charging systems listed, labeled, and identified for more than a single branch circuit or feeder
(8)Docking facilities and piers
225.30(B) Common Supply Equipment.
Where feeder conductors originate in the same panelboard, switchboard, or other distribution equipment, and each feeder terminates in a single disconnecting means, not more than six feeders shall be permitted. Where more than one feeder is installed in accordance with this section, all feeder disconnects supplying the building or structure shall be grouped in the same location, and the requirements of 225.33 shall not
apply. Each disconnect shall be marked to indicate the load served. 225.30(C) Special Occupancies.
By special permission, additional feeders or branch circuits shall be permitted for either of the following:
(1) Multiple-occupancy buildings where there is no space available for supply equipment accessible to all occupants
(2) A single building or other structure sufficiently large to make two or more supplies necessary
225.30(D) Capacity Requirements.
Additional feeders or branch circuits shall be permitted where the capacity requirements are in excess of 2000 amperes at a supply voltage of 1000 volts or less.
225.30(E) Different Characteristics.
Additional feeders or branch circuits shall be permitted for different voltages, frequencies, or phases, or for different uses such as control of outside lighting from multiple locations.