Earth Cable Sizing Chart !exclusive! -

Similar to IEC, but with local tables.

Fault current at machine = 4 kA (calculated). Step 2: From IEC-style table (k=143, 0.2 s): ( S = \frac\sqrt4000^2 \times 0.2143 \approx \frac1789143 \approx 12.5 \text mm^2 ) Step 3: Nearest standard size = 16 mm². Step 4: Check table lookup (fault current 4 kA → min 6 mm²). But our length 50 m: Earth loop impedance must allow >100 A to trip breaker. If 16 mm² gives 0.25 Ω loop, fault current = 400/0.25 = 1600 A (too low for 100 A breaker to trip in 0.2 s? Actually 1600 A is fine, but 6 mm² would give ~0.4 Ω, 1000 A – still trips but slower). The 16 mm² is safer and required by adiabatic. Final choice: 16 mm². earth cable sizing chart