@Saskguy 

Here is the recommendations we have with respect to the ground wire:

Not all wall switches are connected to ground wires and not all junction boxes have a ground wire accessible.

• If your junction box is plastic and no ground wire was connected to your old switch, there may be a bundle of bare copper or green wires in the back of the junction box. You will need to unfold this bundle and connect the green ground wire from HS210 using a wire nut.
• If your junction box is plastic and no ground wire is present, you can simply cap the ground wire on HS210 with a wire nut. 
• If your junction box is metal, there may not be a ground wire present; in this case, you should be able to connect your ground wire to the box itself.

@Tony FYI, the GREEN ground wire only comes thru the switch and is attached to the metal tab/plate behind the top.

There is no internal connection and has no function that l can explain.