What is typically designated as the main control point and cutoff of the electrical supply?

The main control point and cutoff of the electrical supply is generally designated as service equipment. Service equipment refers to the equipment necessary to deliver electrical energy to a building or structure from the utility source, which includes the service entrance conductors, metering equipment, disconnect devices, and overcurrent protection. This equipment is crucial because it manages the entire electrical service and ensures that the electrical system can be safely de-energized when needed, such as for maintenance or emergencies.

While the main circuit breaker is also essential, as it provides a point of disconnection, the term service equipment encompasses a broader range of components that contribute to the overall management and control of the electrical supply. Thus, service equipment is typically recognized in the NEC as the primary point for controlling and cutting off electrical service.

Power control units and distribution boards serve specific functions in the distribution and management of electrical circuits within a building but do not serve as the main cutoff for the entire electrical supply.