标准摘要
[中文适用范围]： 本文件规定了用于测量线路导体与保护导体之间、线路导体与中性线之间或两个线路导体之间环路阻抗的设备的适用要求，测量方法是在测试电路加载时利用电压降。 [外文原描述]： IEC 61557-3:2019 specifies the requirements applicable to equipment for measuring the loop impedance between a line conductor and protective conductor; between a line conductor and neutral; or between two line conductors by using the voltage drop when the circuit under test is loaded. IEC 61557-3:2019 cancels and replaces the second edition published in 2007. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) addition of equirements as regards the measurement category; b) addition of new requirements for operating instructions; c) alignment of the structure with that of the whole IEC 61557 series.
英文名称Electrical safety in low voltage distribution systems up to 1 000 V AC and 1 500 V DC - Equipment for testing, measuring or monitoring of protective measures - Part 3: Loop impedance