WireFillChart provides reference data and calculators based on the National Electrical Code (NFPA 70), 2023 edition. Code adoption varies by state and municipality — your local jurisdiction may enforce an earlier or later edition, or may amend specific articles.
Calculator outputs ignore project-specific factors that may legally bind your installation, including:
- Ambient temperature derating (NEC 310.15(B)(1)).
- Ampacity adjustment for > 3 current-carrying conductors (NEC 310.15(C)(1)).
- Conduit routing, bends, and pull tension limits.
- Manufacturer-specific termination ratings (60/75/90 °C).
- Hazardous (classified) location requirements.
Always have safety-critical work designed, installed, and inspected by individuals licensed to perform electrical work in your jurisdiction. WireFillChart accepts no liability for installations made in reliance on the site's output.