This tool examines the mechanical systems that you create in a project to verify that each system is assigned to a user-defined system, and properly connected.
Showing Disconnects
You can display disconnect markers for connectors that are not currently connected. To control the display of disconnect markers, click Analyze tab
Check Systems panel
Show Disconnects. In the Show Disconnects Options dialog, select one or more of the following:
Check Systems panel Show Disconnects. In the Show Disconnects Options dialog, select one or more of the following: - Duct
- Pipe
- Cable Tray and Conduit
- Electrical
- Fabrication Hanger
In the following example, Duct disconnect markers were selected.
Click a warning marker to display a related warning message. Click 
Expand Warning Dialog to view the details of the warning message.
Click Show Disconnects and clear the selections to turn off the disconnect markers.