pulse train relay

例句：

1. 1. The pulse train relay is used to control the speed of the train.
   脉冲式列车继电器用于控制火车的速度。
2. 2. The pulse train relay is an important component in the electrical system.
   脉冲式列车继电器是电气系统中的一个重要组成部分。
3. 3. The pulse train relay is responsible for detecting and responding to signals from the train.
   脉冲式列车继电器负责检测并响应来自火车的信号。