IEC 61643-21:20 0+A1:2008适用于电信和信号网络电涌保护设备，防止闪电或其他瞬态过电压的间接和直接影响。这些SPD的目的是保护连接到标称系统电压高达1 000 V（r.m.s.）交流电的电信和信号网络的现代电子设备。和1500V直流电。2001年3月更正的内容已列入本副本。 本合并版本由第一版（2000年）组成 及其修正案1（2008）。因此，无须在 本出版物的补充。

IEC 61643-21:2000+A1:2008 is applicable to devices for surge protection of telecommunications and signalling networks against indirect and direct effects of lightning or other transient overvoltages. The purpose of these SPDs is to protect modern electronic equipment connected to telecommunications and signalling networks with nominal system voltags up to 1 000 V (r.m.s.) a.c. and 1 500 V d.c. The contents of the corrigendum of March 2001 have been included in this copy. This consolidated version consists of the first edition (2000) and its amendment 1 (2008). Therefore, no need to order amendment in addition to this publication.