I believe the actor you are referring to is Bill McKinney. He plays Jack Van Hay in The Green Mile. His IMDb page is linked below if you'd like to view some of his other acting roles.
Further Reading
The Green Mile
by Stephen King
Who played the executioner that ran the generator and threw the switch in the movie The Green Mile, and where have I seen him before? The guy is only in a few scenes, he's wearing a black rubber glove and stands behind a partition. I know i've seen him in other films or tv or somewhere.