Ground-fault protection is required for a feeder disconnect if what condition exists?

Ground-fault protection is essential for feeder disconnects to ensure safety against electrical faults that may cause hazards like electrocution or fire. The requirement for ground-fault protection is derived from the necessity to protect personnel and equipment from ground faults, which can lead to unsafe conditions.

The condition that necessitates ground-fault protection for a feeder disconnect addresses various scenarios including the presence of multiple feeders and the capacities of conductors. Ground-fault protection is particularly crucial when there are larger conductors or multiple feeders involved as higher amperage indicates an increased risk for serious faults.

In this context, if all the conditions listed in the options are met, ground-fault protection is required to ensure comprehensive safety measures are in place. This includes protecting multiple feeders, safeguarding feeders rated above 100 amperes, and ensuring that the protection is not limited to just the main disconnect. Each part contributes to a holistic safety strategy, reinforcing the need for ground-fault protection across the entire electrical system.