Determine the optimal wire size for your 100 amp electrical circuits with our precise online calculator. Ensure electrical safety, prevent voltage drop, and comply with NEC standards for residential, commercial, and industrial applications. Get accurate AWG recommendations instantly for copper and aluminum conductors.
Formula:
The calculator considers several factors to determine the appropriate wire size (AWG/kcmil), primarily focusing on Ampacity, Voltage, Distance, Conductor Material, and Allowable Voltage Drop. While a direct algebraic formula for AWG isn't common, the underlying principle often involves ensuring voltage drop remains within acceptable limits (typically 3%):
Vdrop = (2 × K × I × L) / A
Where:
Vdrop = Voltage Drop (Volts)
K = Conductor Resistivity (Copper ≈ 12.9, Aluminum ≈ 21.2 at 75°C)
I = Current (Amps) - Fixed at 100 Amps for this calculator
L = One-way Circuit Length (feet)
A = Conductor Area (Circular Mils)
Our calculator simplifies this by providing an AWG recommendation based on these inputs, ensuring both ampacity and voltage drop requirements are met.