We have a wooden chicken coop inside a fenced run. As it stands now, we have an opening through the fence in the run that we open in the mornings so that the chickens can free range during the day. We then close up that opening after the chickens have come in for the night. We want to get an electronic door opener so that we can be assured of closing the chickens in when we cannot get home by dark. Should we put this door opener on the actual door of the coop, or should we put it on the opening going out for free ranging?