ICC Residential Electrical Inspectors Practice Exam

What maximum conductor temperature rating should be used for type SE cable feeders when determining final ampacity inside a building?

1. 40 degrees Celsius

2. 50 degrees Celsius

3. 60 degrees Celsius

4. 75 degrees Celsius

The correct answer is: 60 degrees Celsius

When determining the final ampacity of type SE cable feeders inside a building, it's essential to refer to the applicable code regulations regarding conductor temperature ratings. Type SE (Service Entrance) cables are designed for specific applications, and their thermal performance is a key factor in ensuring safety and reliability. The maximum conductor temperature rating that should be used for these cables when assessing their ampacity is specifically 60 degrees Celsius. This rating is based on the material of the conductors used within the type SE cable and the typical operating conditions found within residential environments. Using a 60 degrees Celsius temperature rating allows for a standardized analysis of the cable's capability to safely carry electrical current. It ensures that the cable can handle the heat generated by the electrical load without exceeding its temperature limits, thereby preventing potential overheating, insulation degradation, and associated safety hazards. This rating is crucial in practical applications since it aligns with the code and safety practices for residential electrical installations, which are intended to protect wiring integrity and reduce risks associated with electrical fires or failures. Therefore, using 60 degrees Celsius for type SE cable feeders when determining final ampacity inside a building provides the necessary safety margin while adhering to the regulatory framework established for electrical installations.