| 摘要 |
PROBLEM TO BE SOLVED: To provide a digital output holding device easily exchanging digital output cards with a simple configuration during maintenance or when exchanging cards because a failure occurs in a digital output card, or the like. SOLUTION: The digital output holding device 50a in which an external digital output card 20 outputs an output signal in response to an instruction from an external controller 10, and an external I/O terminal unit 30 having a relay to be turned on/off in accordance with the output signal outputs a control signal in accordance with an excitation state of the relay and outputs a same signal as the control signal in controlling an external control target 40, is provided with a first detecting part 52a for detecting an output signal of the digital output card 20, a hold signal generating part 56a for generating a hold signal same as the output signal detected by the first detecting part 52a, and a hold signal output part 58a for outputting the hold signal generated by the hold signal generating part 56a to the control target 40 through the I/O terminal unit 30. COPYRIGHT: (C)2008,JPO&INPIT
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