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How to Size Electrical Wire
Formula
Correct wire gauge prevents overheating, voltage drop, and code violations. Longer runs and higher currents require thicker wire.
The NEC recommends no more than 3% voltage drop for branch circuits and 5% total from the panel to the outlet.
Common use cases:
- Residential wiring projects
- Subpanel feeder sizing
- Outdoor lighting circuits
Frequently Asked Questions
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