Earth Fault Loop Impedance Estimate

Range: 1–1,000 V

Use the line-to-earth voltage for the fault-current basis, commonly 230 V in an Australian low-voltage single-phase circuit.

Range: 0–10 ohm

Enter measured or sourced external loop resistance up to the circuit origin, in ohms.

Range: 0–10 ohm

Enter sourced external loop reactance up to the circuit origin, in ohms.

Range: 0–10,000 m

The model applies this route length once to the line conductor and once to the protective conductor.

Range: 0.1–1,000 mm2

Enter the installed line-conductor cross-sectional area in mm².

Range: 0.1–1,000 mm2

Enter the installed protective-conductor cross-sectional area in mm².

Range: 0.0001–1 ohm mm2/m

Enter the conductor material value from a traceable source; this illustrative copper value is not an AS/NZS table value.

Range: 0–0.02 per C

User-entered material coefficient. Verify it for the selected conductor.

Range: -50–200 C

Enter the temperature at which the supplied resistivity value applies.

Range: -50–250 °C

Use the temperature appropriate to the resistance estimate. The resulting temperature factor must remain positive.

Range: 0–10 ohm/km

Use cable-manufacturer data. Set to zero only when intentionally making a resistance-only estimate.