摘要 |
In a field apparatus control system, one of duplicated main control units and one of communication control units constitute a normal system, and the other of the duplicated main control units and other of the communication control units constitute a standby system. Each of the normal system of communication control unit and the standby system of communication control unit has a same address on a network via the field bus, which is allocated to each of the normal and standby systems of communication control systems. The information that is outputted to the address from the field apparatus via the field bus is transmitted to the normal and standby systems of communication control units, respectively. |