What does the term “de-rating” refer to in electrical wiring?

The term "de-rating" in electrical wiring specifically refers to reducing the allowable ampacity of conductors. This adjustment is made to ensure safety and compliance with certain conditions that may affect the wire's capacity to carry current. Factors such as high ambient temperature, grouping of conductors, or other environmental conditions can require a decrease in the amount of current a wire can safely handle to prevent overheating and associated hazards.

For instance, if wires are bundled together or are subjected to high temperatures, their ability to dissipate heat diminishes, which necessitates a lower ampacity to maintain safety standards. Thus, de-rating helps in preventing failures which might cause short circuits, fires, or other electrical hazards. The other options either do not directly relate to the concept of de-rating or involve different actions not associated with reducing ampacity.