CADWorx Plant I tab: 2D > Zoom Lock 
This ribbon option is only available in CADWorx Plant Professional.
Plant menu: Utility > Zoom Lock
Settings toolbar:
The Settings toolbar Zoom Lock option is only available in CADWorx Plant Professional.
Command line: ZOOMLOCK
Locks the CAD platform ZOOM command to allow zooming in paper space only. This means that while you are in paper space with the MSPACE command activated (the cursors are in the Mview), you can zoom without resizing the model space viewport. Instead, this command intercepts the ZOOM command and changes to paper space before zooming. When you are finished zooming, the command returns the cursor and environment back to the Mview.
This command simplifies working on CADWorx isometrics.
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