Not professional electrical advice. The calculators and articles on this website are for education and estimating only.
- Check your local code. Results are based on the National Electrical Code (NFPA 70), 2017–2023 editions. Your jurisdiction may enforce a different edition or local amendments, and the authority having jurisdiction (AHJ) has the final say.
- Conditions of use matter. Actual wire dimensions, compact or specialty insulation, cable types, ambient conditions, terminal ratings, bends, pulling tension and manufacturer instructions can all change the correct answer.
- Hire a qualified person. Electrical work can cause fire, injury or death. Work should be designed and installed by a licensed electrician, and permits and inspections obtained where required.
- No warranty. We work hard to keep the data accurate but make no guarantee that the results are complete, current or error-free.
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