According to NEC 200.4(A), neutral conductors shall not be used for more than one branch circuit, multiwire branch circuit, or set of ungrounded feeder conductors unless specifically permitted elsewhere in the Code. What is the primary restriction?

• A neutral can only serve one branch circuit or one multiwire branch circuit
• A neutral can serve multiple circuits if they are on the same phase
• A neutral must be sized at 125% of the load
• A neutral can serve unlimited circuits if properly identified