The Highlight Uncircuited Devices command is used to highlight all of the devices on the current drawing that have not yet been circuited.
To highlight uncircuited devices, go to
Ribbon: DM Electrical->Circuiting and Homeruns-> 
Highlight Uncircuited Devices
Pulldown Menu: DM Electrical->Circuiting and Homeruns->Highlight Uncircuited Devices
A line will be drawn from the origin to each device that is not circuited. The lines can be erased using standard CAD commands when you no longer need them.
Running the command a second time on a drawing will remove any lines pointing to devices that are now circuited.