标准摘要
[中文适用范围]： IEC 61557 本部分规定了在不接地的 IT 交流系统和带有 galvanically 连接的直流电路的不接地 IT 交流系统中（标称电压高达 1 000 V 交流），以及在不接地 IT 直流系统中（电压高达 1 500 V 直流）进行绝缘故障定位的绝缘故障定位系统（IFLS）的要求，且独立于测量原理。IT 系统在 IEC 60364-4-41 等文献中有描述。应在其他标准中注意一些设备的选择数据。 [外文原描述]： IEC 61557-9:2014 specifies the requirements for the insulation fault location system (IFLS) which localizes insulation faults in any part of the system in unearthed IT a.c. systems and unearthed IT a.c. systems with galvanically connected d.c. circuits having nominal voltages up to 1 000 V a.c., as well as in unearthed IT d.c. systems with voltages up to 1 500 V d.c., independent of the measuring principle. IT systems are described in IEC 60364-4-41 amongst other literature. Additional data for a selection of devices in other standards should be noted. This third edition cancels and replaces the second edition published in 2009. This edition constitutes a technical revision which includes the following significant technical changes with respect to the previous edition: - the scope, normative references, terms and definitions have been complemented; - abbreviations are listed and explained; - requirements, marking and operating instructions have been revised; - mandatory and optional functions have been defined and their terminology has been adapted to IEC 61557-15; - mechanical requirements have been added; - Clause 6 "Tests" has been revised; and - new Tables have been added. This publication is to be read in conjunction with IEC 61557-1:2007 . The contents of the corrigenda of May 2016 and of January 2017 have been included in this copy.
英文名称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 9: Equipment for insulation fault location in IT systems