Ground Rod Calculator
Calculate ground rod resistance using soil resistivity, rod length, and diameter.
How to Use the Ground Rod Calculator
- Enter soil resistivity in Ω·m.
- Enter the ground rod length in metres.
- Enter the rod diameter in metres.
- Check if resistance meets the NEC 25 Ω limit.
Casos de Uso
- •Grounding system design
- •Lightning protection
- •Electrical safety compliance
Fórmula
R = (ρ / 2πL) × (ln(4L/d) − 1)
Preguntas Frecuentes
How accurate is this calculator?
Results are based on standard engineering formulas and are suitable for preliminary estimates.
What units are used?
SI units (metres, kg, kPa) are used unless otherwise noted.
Is it free?
Yes, all calculators are completely free.