Protection & Fault Analysis Calculators

Verify earth fault loop impedance, prospective fault current, protective conductor sizing, device selection, and discrimination to BS 7671.

Ze — External earth fault loop impedance (Ω)

Cable length (m)

R1 — Line conductor cable size

R2 — CPC cable size

Apply temperature correction factor (1.20 for PVC at 70°C)

Protective device type (optional)

Device rating (A)

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