本标准规定了用于低压通信电路浪涌保护的串联自恢复限流器组件的术语、试验方法、试验电路、测量程序和首选结果值。本标准仅适用于电信电路中的元件，其正弦振铃电压在15 Hz至70 Hz时高达150 V rms，直流供电电压高达400 V。本标准涵盖的自恢复电流限制器具有以下特性: -电流过大会导致从低电阻状态过渡到高电阻状态 -当过大电流结束时，恢复到低电阻状态 -由流经组件的电流直接操作 -固态（无活动部件） -能够承受指定的冲击水平 -在高电阻状态下承受规定的交流电压水平 这种限流器技术的例子包括陶瓷或聚合物材料的正温度系数（PTC）阶跃函数限流器和基于硅半导体的电子电路。 本标准不包括其他应用中使用的自恢复限流器组件，如加热器、浪涌电流限制器或传感装置。电流中断型组件，可降低 本标准不包括因机械电路断路而变为零的电流。在本标准中，电信电路是一种使用金属导体处理远程信息传输（如数据、通信和信号）的电路。

This standard sets terms, test methods, test circuits, measurement procedures and preferred result values for series connected, self-restoring current-limiter components used in low-voltage telecommunication circuit surge protection. It is only applicable for components in telecommunications circuits with sinusoidal ringing voltages up to 150 V rms at 15 Hz to 70 Hz and dc powering voltages up to 400 V. The self-restoring current limiters covered by this standard have the following properties: - Excessive current causes a transition from a low-resistance state to a high-resistance state - Reverts to a low-resistance state when the excessive current ends - Directly operated by the current flow through the component - Solid-state (no moving parts) - Withstands specified levels of impulse - Withstands specified ac voltage levels when in the high-resistance state Examples of this type of current-limiter technology are positive temperature coefficient (PTC) stepfunction theremistors of ceramic or polymeric material and silicon semiconductor based electronic circuits. This standard does not cover self-restoring current-limiter components used in other applications, such as heaters, inrush-current limiters, or sensing devices. Current interrupting type components, which reduce the current to zero by a mechanical circuit break, are not covered by this standard. In this standard, a telecommunications circuit is a circuit that uses metallic conductors to handle the remote transmission of information, such as data, communications, and signalling.