| 摘要 |
<p>PURPOSE: To provide a digital controller which can carry out the precise tests of the input/output substrates included in a controller in a plant operation mode. CONSTITUTION: A digital controller is provided with a controller 1 which has the #1 to #N AO substrates 3 to 4 and outputs the control signals from these substrates through the output lines to control the #1 to #N controlled systems 7 to 8 that are connected to the output lines, a switch circuit 23 which periodically separates those output lines from the systems 7 to 8, a test device 15 which tests the soundness of the control signal acquired from the output lines of one of systems 7 to 8 that is separated from its output line, and a backup AO substrate 19 which outputs a signal equivalent to the control signal to the output line of the separated controlled system to control this system in a test mode of the device 15.</p> |
