What is the subject of Annex C in the NEC®?

Annex C of the National Electrical Code (NEC®) specifically addresses conduit and tubing fill tables. This annex provides essential charts and tables that electricians and engineers use to determine the maximum number of conductors that can safely be contained within various sizes and types of conduits and tubing. This information is crucial for ensuring that electrical installations are not only efficient but also compliant with safety standards, as overcrowding conduits can lead to overheating and potential electrical failures.

Understanding these fill tables helps practitioners maintain adherence to safety protocols while designing and installing electrical systems, which is fundamental in preventing electrical hazards. The tables provide detailed guidance based on different conductor sizes, which allows for proper planning and execution of electrical installations.