| 摘要 |
PURPOSE:To make least the lowering in the operation rate of the entire system and to increase the safety, by retrieving the remote input and output unit of the group belonging to the remote input and output unit in failure, stopping it to safety side, and avoiding the effect on other group units. CONSTITUTION:The central unit 1 consists of CPU, program memory unit PM, and input and output data memory unit DM, and the remote input and output unit RIO-1...RI-4 include the group number set units GN1...GN4. If the unit RIO-1 is in failure and the operation is stopped, CPU confirms this via the managing file and the one belonging to the same group as RIO-1 is retrieved, and if it is found, the stop instruction is made to the unit RIO-2 and stops it to safety side. Thus, no effect on other units is given and the lowering in the operation rate of the entire system can be minimized to increase the safety. |
