To modify a low voltage device that is inserted on the drawing, go to
Ribbon: DM Electrical->Devices-> 
Query Device
Pulldown Menu: DM Electrical->Modify Devices->Query Device
Select a low voltage device on the drawing. The information in the database regarding the selected low voltage device will be displayed in the Query Low Voltage Device dialog box.
Query Low Voltage Device Dialog Box
Changes can be made to the low voltage device in the same way as when it was inserted. See the Insert Low Voltage Device section for more information.