🔌 Voltage Drop Calculator
Calculate voltage drop for electrical circuits with NEC compliance checking, temperature correction, and wire size recommendations.
Circuit Parameters
AWG 12 Wire Properties
Wire Resistance Reference (Ω/1000 ft)
| AWG Size | Copper | Aluminum |
|---|---|---|
| AWG 4/0 | 0.049 | 0.080 |
| AWG 3/0 | 0.062 | 0.101 |
| AWG 2/0 | 0.078 | 0.127 |
| AWG 1/0 | 0.098 | 0.160 |
| AWG 1 | 0.124 | 0.202 |
| AWG 2 | 0.156 | 0.254 |
| AWG 4 | 0.249 | 0.406 |
| AWG 6 | 0.395 | 0.644 |
| AWG 8 | 0.628 | 1.024 |
| AWG 10 | 0.999 | 1.628 |
| AWG 12 | 1.590 | 2.592 |
| AWG 14 | 2.520 | 4.108 |
| AWG 16 | 4.020 | 6.553 |
| AWG 18 | 6.390 | 10.416 |
Understanding Voltage Drop
Voltage drop occurs when current flows through wire resistance, reducing the voltage available at the load.
NEC Guidelines: The National Electrical Code recommends limiting voltage drop to 3% for branch circuits and 5% total for combined feeders and branch circuits.
Formula: Voltage Drop = 2 × K × I × L / CM, where K is the resistivity constant, I is current, L is one-way length, and CM is circular mils.
Why it matters: Excessive voltage drop can cause equipment malfunction, motor overheating, lamp dimming, and energy waste.
Disclaimer
This calculator is provided as-is for educational and informational purposes only. While we strive for accuracy, always verify calculations with professional standards and local electrical codes. Use at your own risk. For critical applications, consult a licensed professional electrician.
Optimize Every Run
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- TempConvert — Lightning-Fast Temperature Converter
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