Meaning of Branch Circuit
A branch circuit is a particular type of circuit that runs from a circuit breaker panel to devices in a building. Branch circuits are classified as general purpose, appliance, or individual circuits, depending on their function.
A circuit is made up of a wire that connects a power source to fuses, switches, and a load. The load is the device that consumes the energy flowing through the circuit, such as the bulb in a lamp.
A washing machine on an appliance branch circuit.
Any building connected for electricity has a circuit breaker panel. This panel is usually a metal box or cabinet filled with switches and mounted on the wall.
Each switch is connected to an electrical circuit in the home and can cut power to that circuit if it is turned off. A branch circuit runs from each switch to the building’s receptacles, light fixtures, and appliances.
Branch circuits run from the breaker box to appliances and outlets throughout the building.
The purpose of a branch circuit is to supply power to electrical devices in the home. Each consists of a loop of wire running from the breaker panel to the lights and receptacles and back again. They are classified according to their current charging capacity and the type of devices they serve.
A general purpose branch circuit is a 120-volt circuit that supplies power to lighting fixtures and outlets. Modern general circuits use 12-gauge wire and are rated for a maximum of 20 amps (amps).
Amps refers to the amount of electrical charge that passes through any point in the circuit during a unit of time. In older buildings, 14-gauge wire was used to build branch circuits rated for no more than 15 amps. Fifteen amps is no longer considered enough for most homes.
Power is supplied to fixed electrical devices such as refrigerators, washing machines, and dishwashers through an appliance branch circuit.
Like general purpose circuits, appliance circuits also carry 120 volts and cannot exceed 20 amps. They do not supply power to any type of luminaire.
An individual branch circuit supplies power to a specific device, usually a permanent fixture such as a clothes dryer or electric range. Since the circuit works with only one device, the power to that device can be cut without affecting the electricity supply to the rest of the building.
This is useful if there is a fire or if the device needs maintenance. These circuits vary in amperage depending on the appliance they are intended for.
A fuse is a key part of an electrical circuit.