标准摘要
[中文适用范围]： 本部分IEC 60947规定了三位使能开关的要求。这些开关用作使能装置的组件，提供如下信号：a) 激活时，允许通过单独启动控制启动机器运行；b) 非激活时，启动停止功能并防止启动机器运行。这些开关旨在连接额定电压不超过250 V AC 50 Hz/60 Hz或300 V DC的电路。 [外文原描述]： IEC 60947-5-8:2020 specifies requirements for three-position enabling switches. These switches are used as components of enabling devices to provide signals that, - when activated, allow machine operation to be initiated by a separate start control, and - when de-activated, -- initiate a stop function, and -- prevent initiation of machine operation. This second edition cancels and replaces the first edition published in 2006. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: - due to the increasing range of useful applications of three-position enabling switches, note of scope, operational characteristics and tests are reviewed; - figures for example of devices incorporating enabling switch are added in Annex A; - new Annex B for procedure to determine reliability data for the switch used in functional safety applications is added.
英文名称Low-voltage switchgear and controlgear - Part 5-8: Control circuit devices and switching elements - Three-position enabling switches