Digital Output Tag Type Properties: Feedback Tab
The Feedback tab can be used to select an existing tag, or create a new tag belonging to the Digitals Group, that will provide feedback indicating the current status of this tag's control action.
When the feedback tag’s value changes to what was expected as a result of the digital output, then the digital output tag’s value will go to 0, indicating that no output is in progress (i.e. the write has finished)
Until the feedback tag changes to the value expected as a result of the digital output (perhaps because a communication error is preventing the output from occurring) then the digital output tag’s value will remain at 1, indicating that the output is still in progress.
If the feedback tag’s value changes independently of a write occurring from the digital output, the tag’s value will undergo a transitory change to a 2. This signal is designed for the use of VTS programmers – it does not last long enough to be displayed and cannot be captured by an alarm.
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Select or create a tag from the digitals group that will provide the source of the feedback.
The Feedback At State 0 spin box can be used to set the value you expect back from the feedback tag when the digital output has successfully written a 0 (State 0).
The Feedback At State 1 spin box can be used to set the value you expect back from the feedback tag when the digital output has successfully written a 1, 2 or 3 (State 1).