Short-Circuit Protection for Service Entrance Conductors and Switchboards

To provide a higher degree of safety and service continuity, particularly in commercial buildings, it is recommended that the low-voltage electric system be broken into a larger number of smaller separate main switchboards, each fed by a separate service-entrance busway or with cables. Each service-entrance protective device would be mounted in a separate enclosure located on the input end of the service-entrance conductors and as close as practicable to the point where the service enters the building. Should an accidental arcing fault occur, such a design will prevent loss of power to any large area of the building.