Which factor must be considered when sizing conductors for feeders?

When sizing conductors for feeders, the temperature rating of the insulation is a critical factor because the insulation material must be able to withstand the heat generated by the electrical current flowing through the conductor. Conductors carry current, and as they do so, they generate heat due to resistance. If the temperature exceeds the rated limit of the insulation, it can lead to degradation or failure of the insulation material, which poses safety hazards such as short circuits or fires.

Selecting the appropriate conductor size based on the temperature rating ensures that the feeder can operate within safe limits, maintaining not only the integrity of the installation but also the safety of the overall electrical system. This consideration also directly impacts the performance and reliability of the electrical system, as conductors that are too small for a given load may overheat, while those that are oversized can be unnecessarily costly and cumbersome.