KS IEC 61557-3:2019

Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. - Equipment for testing, measuring or monitoring of protective measures-Part 3:Loop impedance.

Specifies the requirements applicable to equipment for measuring the loop impedance between a phase conductor and the protective conductor or between a phase conductor and neutral or between two phase conductors by using the voltage drop when the