Controller build - 3 axis cnc router

In my build i have a central Earth Grounding point where all my earth connections run to.
I also have a separate central point for my DC common ground connections.

The build is complete and up until now there has not been any continuity between the two points listed above, but when I plug the VGA cable of my monitor into the control board, my central Earth Ground point and central DC Common point become connected.

Note: This is due to the VGA socket on the control board being grounded to the control board Ve- terminals and the VGA monitor cord being grounded to the Earth Ground wire in my monitor's power cord. So the connection is being made within the wall sockets which in turn link my two distribution blocks within the cabinet.

Can anyone tell me if this is normal? Can a ground loop occur if the central Earth Ground point is connected to the central Common ground point?