A continuous load rating generally requires overcurrent protection to be rated at what value?

For a continuous load rating, the requirement for overcurrent protection is to be rated at 125% of the load. This means that if a load is classified as continuous, it is expected to operate at its maximum capacity for three hours or more. The rationale behind using 125% is to ensure there is a safety margin that accommodates any potential overload conditions without tripping the circuit breaker too easily during normal operation.

When a load consistently approaches its maximum rating, it can generate more heat than anticipated, which increases the risk of overheating and potential failures. By setting the overcurrent protection at 125%, it allows for up to 25% more current than the continuous load without tripping, thereby enhancing safety and stability in the electrical system. This practice aligns with NEC (National Electrical Code) guidelines, promoting both the safe use of electrical systems and operational efficiency.