To what types of load combinations does the requirement for overcurrent protection for feeders apply?

The requirement for overcurrent protection for feeders applies to both continuous and noncontinuous load combinations because these loads can significantly impact the electrical system's performance and safety. Continuous loads are those that are expected to operate for three hours or more, while noncontinuous loads operate for shorter durations.

In the context of feeder circuits, which are responsible for distributing power to branch circuits, it's crucial to ensure that they can safely handle both types of loads under normal operating conditions. Overcurrent protection is designed to prevent overheating and potential fire hazards by interrupting the circuit when the current exceeds the safe capacity.

By including both continuous and noncontinuous loads in the requirement, the electrical system is safeguarded against the potential effects of sustained overcurrent scenarios, as well as short-term surges. This comprehensive approach ensures that feeders are adequately protected in various operational scenarios, aligning with the National Electrical Code's (NEC) emphasis on safety and reliability.