该系统具有控制装置（1），即可编程控制器，其中连接有总线用户，其中用户具有分配器（3），子总线系统的子总线分配器（5a-5d）连接到该分配器。 分配器（3）具有电压监视装置（7），用于监视与副总线分配器相对的供电电压。 子总线分配器具有报警释放装置，用于在电压低于最小电源电压时释放报警。 释放装置具有用于将报警释放到分配器或控制装置的控制装置。

Bus system with a control device (1), in particular a programmable logic controller, are attached to which bus participants can be connected, comprising at least one manifold (3), can be connected to the turn, preferably connected in series Subbusverteiler (5) of a Subbussystems, each having a device (7 ) have to monitor the voltage present at Subbusverteiler supply voltage and connections (6), characterized in that the Subbusverteiler (5) are further provided with a means for generating an alarm when falling below a minimum supply voltage.