IEC 62271-104:2020适用于额定电压高于52 kV的三极交流开关，具有额定电流和断开电流，适用于室内和室外安装，以及额定频率高达60 Hz（含60 Hz）。 这第三版取代并取消了2015年出版的第二版。它构成技术修订。 与上一版相比，此版本包括以下重大技术变更: -新编号，遵循IEC 62271-1:20 17。

IEC 62271-104:2020 is applicable to three-pole alternating current switches for rated voltages higher than 52 kV, having making and breaking current ratings, for indoor and outdoor installations, and for rated frequencies up to and including 60 Hz.
This third edition replaces and cancels the second edition published in 2015. It constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
– new numbering, following IEC 62271-1:2017.