在总线制火灾报警控制系统的调试工作中 ,是否遇见过这样的问题 :火灾报警控制器已经发出了控制指令 ,控制模块也已经动作 ,但一些外部控制设备如排烟阀、送风口之类就是不能动作。我们在现场使用万用表监测控制模块 DC2 4 V输入端的电压 ,发现在报警器没有发出控制指令前 ,电 In the bus-based fire alarm control system debugging, have encountered such a problem: the fire alarm controller has issued a control command, the control module has also been action, but some of the external control devices such as exhaust valves, air outlets and the like is Can not move. We use the multimeter in the field to monitor the voltage of the DC2 4 V input of the control module and found that before the alarm did not issue a control command,