What are multi-wire branch circuits?

Multi-wire branch circuits are characterized by their use of two or more hot wires that share a single neutral wire. This approach allows for more efficient use of wiring and can reduce the amount of copper needed in a given installation. Additionally, when the circuit is properly designed and balanced, it can enhance safety and functionality by distributing the load across the hot conductors and returning through a common neutral.

Utilizing multiple hot wires that share a neutral can also allow for 240-volt service where needed, depending on the configuration of the hot wires, thereby providing versatility for various electrical loads. The correct design and implementation of multi-wire branch circuits are essential to ensure that they operate safely, as overloading the shared neutral wire should be prevented to avoid potential hazards.

In contrast, circuits that use a single hot wire for multiple outlets are simpler and don’t offer the same advantages as a multi-wire configuration. Circuits limited to operating on only 120 volts do not provide the broader capabilities of a multi-wire branch circuit, which can operate at higher voltages depending on the setup. Lastly, while multi-wire branch circuits can be used in residential settings, they are not limited to them and can also be found in commercial or industrial applications.