| 摘要 |
PROBLEM TO BE SOLVED: To provide a process control device capable of reducing the fluctuation of output currents when any failure occurs in a part of a output system, and restoring an original level in a short time. SOLUTION: The process control device includes a redundant analog signal output circuit for output of a current signal for controlling an object to be controlled. A process control arithmetic part (digital controller), by comparing a digital output value by instructing the analog signal output circuit with the results of the analog conversion of the digital output value, detects the failure of the analog signal output circuit, separates the circuit which the failure has been detected, and instructs each analog signal output circuit which has not been broken down in the uniform digital output value so that the current signal to be output to the object to be controlled can be obtained by synthesizing current signals to be uniformly output from one or more analog signal output circuits which have not been broken down. COPYRIGHT: (C)2011,JPO&INPIT |
