Calculator Inputs
Use preset material values or switch to custom data. The form uses a responsive 3-column, 2-column, and 1-column arrangement.
Example Data Table
The following example values show how conductivity and resistance change with temperature for a 10 m copper conductor with 16 mm² area.
| Case | Temperature (°C) | Purity (%) | Conductivity (MS/m) | Resistance (Ω) | %IACS |
|---|---|---|---|---|---|
| Low Temperature | 20 | 100 | 58.001 | 0.010776 | 100.00 |
| Moderate Heating | 60 | 100 | 49.273 | 0.012686 | 84.95 |
| Elevated Temperature | 90 | 99.5 | 43.508 | 0.014368 | 75.01 |
Formula Used
1) Temperature-corrected resistivity
ρ(T) = (ρref / purity_fraction) × [1 + α × (T − Tref)]
2) Conductivity
σ = 1 / ρ(T)
3) Resistance from geometry
R = ρ(T) × L / A
4) Conductance
G = 1 / R
5) Percent IACS
%IACS = [σ / 58,000,000] × 100
6) Voltage drop and power loss
Vdrop = I × R and Ploss = I² × R
7) Current density
J = I / A(mm²)
8) Skin depth
δ = √[2ρ / (ωμ)], where ω = 2πf and μ ≈ μ0 for copper.
How to Use This Calculator
- Select a material preset or choose custom input.
- Enter operating temperature and reference temperature.
- Provide purity, reference resistivity, and temperature coefficient.
- Enter conductor length and cross-sectional area.
- Add current to estimate voltage drop and power loss.
- Add frequency to estimate skin depth.
- Set the graph temperature range and number of points.
- Press Calculate Conductivity to display results above the form.
- Use the CSV and PDF buttons to export the calculated report.
Frequently Asked Questions
1. What does this calculator measure?
It estimates copper resistivity, conductivity, resistance, conductance, percent IACS, voltage drop, power loss, current density, and skin depth using practical engineering inputs.
2. Why does conductivity decrease with temperature?
As temperature rises, copper atoms vibrate more strongly. Electron scattering increases, resistivity rises, and conductivity falls. This effect is commonly modeled with a linear temperature coefficient.
3. What is %IACS?
%IACS compares conductivity to the International Annealed Copper Standard. Around 100% IACS represents high-quality annealed copper at the standard reference condition.
4. When should I use custom values?
Use custom values when working with supplier data, plated conductors, special grades, mixed purity assumptions, laboratory samples, or cases where preset copper properties are not suitable.
5. Why do length and area matter?
Conductivity describes the material itself, but resistance also depends on geometry. Longer conductors increase resistance, while larger cross-sectional area reduces resistance.
6. What is skin depth in this tool?
Skin depth estimates how deeply alternating current penetrates the conductor. Higher frequency reduces penetration, making current crowd toward the surface.
7. Is the purity correction exact?
No. It is a practical approximation. Actual conductivity can also depend on alloying, cold work, grain structure, surface condition, and manufacturing process.
8. Can I use this for cables and busbars?
Yes. It is useful for conductors where you know material properties, temperature, length, area, current, and frequency assumptions for quick electrical estimates.