MCPCalc

Wire Size Calculator

Calculate the recommended wire gauge (AWG) based on amperage, distance, voltage, and wire material using NEC standards.

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What This Calculator Does

Calculate the recommended wire gauge (AWG) based on amperage, distance, voltage, and wire material using NEC standards.

It combines Amperage (A), One-Way Distance (ft), Voltage, Wire Material to estimate Recommended Wire Size, Wire Material, Required Circular Mils.

Formula & Method

Required conductor area in circular mils is CM=\frac{2KIL}{V_d} where K is material resistivity constant, I current, L one-way length, and V_d allowable voltage drop. Recommended AWG is the smallest meeting both circular-mil and ampacity limits.

Notation used in the formulas: R = Recommended Wire Size; x_{1} = Amperage (A); x_{2} = One-Way Distance (ft); x_{3} = Voltage; x_{4} = Wire Material; x_{5} = Max Voltage Drop (\%).

Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.

Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.

Inputs Used

  • Amperage (A): Used directly in the calculation.
  • One-Way Distance (ft): Used directly in the calculation.
  • Voltage: Used directly in the calculation.
  • Wire Material: Used directly in the calculation.
  • Max Voltage Drop (%): Used directly in the calculation.

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