Journeyman Electrician Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

When calculating the rating of the overcurrent device for continuous loads, it is essential to account for the potential impact of these loads on the overall system. Continuous loads are defined as loads that operate continuously for three hours or more. To ensure safety and prevent overheating, the National Electrical Code (NEC) requires that the rating of the overcurrent device must be able to handle not just the load itself, but also an additional percentage to account for increased demand.

The correct approach is to add 125% to the rating of the noncontinuous loads. This accommodates the additional stress placed on the circuit when continuous loads are present, ensuring that the overcurrent protection will not trip inadvertently during regular operation. This practice helps to maintain both safety and functionality within an electrical system.

In contrast, other percentages like 100%, 120%, or 150% do not align with the NEC regulations for continuous load calculations, and using those could compromise the effectiveness of overcurrent protection and increase the risk of electrical failures.