| 摘要 |
PURPOSE:To obtain not only the optimum filter function but the optimum speed of transmission, by making the capacitor of a filter circuit provided at the input side of a process input device variable. CONSTITUTION:The digital on/off information given from the plant 1 is supplied to the process input/output device 5 via a filter circuit 4 consisting of the resistances R1 and R2, variable capacitor 8 plus diodes CR1-CR3. Thus a selection is possible for the value of a capacitor that provides the optimum filter function to the noise caused by the conditions of installation since the capacitor 8 forming the circuit 4 is made variable. As a result, the optimum speed of transmission is obtained. |
