In the high-level elevator supposes to speaks the telephone, the establishment emergency call button, the installment pyroscan;

高层中的电梯内设对讲话机，设置紧急呼叫按钮和门磁控制开关，安装挂墙明装红外幕帘探测器；

youdao

In the high-level elevator supposes to speaks the telephone, the establishment emergency call button, the installment pyroscan;

高层中的电梯内设对讲话机，设置紧急呼叫按钮和门磁控制开关，安装挂墙明装红外幕帘探测器；

youdao