In this guide I will go through how to remove PLC, in order for it not being visible anymore.
Select the "Cogwheel"
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Select "DIAP"
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Choose which DIAP you would like to remove a PLC by pressing the menu button.
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Select the "pencil" of the PLC you wish to remove.
A pop-up will occur. In the bottom of the pop-up the following can be found: 'Is Active'. Slide it to the left, if you wish to determine the PLC is not active anymore.
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After having pressed the slider, then press the "Save changes"
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Now the PLC will be removed / set as inactive.
How to get the inactive PLC shown once again?
Select "Settings"
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Change the setting of 'Show hidden DIAPs, PLCs and Tags:' to "Yes"
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Now the PLC will be shown once again, but still set as inactive.