Where must the location of the circuit disconnecting the primary power be identified?

The circuit disconnecting the primary power must be clearly identified on the circuit breaker itself to ensure that anyone who needs to access or service the electrical system can easily find and operate the disconnect mechanism. This is crucial for safety reasons, allowing for swift deactivation of power in case of an emergency or during maintenance. Clearly labeling the circuit breaker helps ensure that personnel can easily identify which breaker disconnects the power to the circuit they are working on, minimizing the risk of accidental electric shocks or other hazards.

While the main control panel, circuit diagram, and installation manual serve important roles in understanding or documenting the electrical system, they do not provide the immediate and direct identification necessary for circuit disconnection. Therefore, marking the circuit breaker itself is the preferred and safest practice for ensuring quick and necessary access to the primary power disconnect.