I have a switch connected to a duplex receptacle using 14-3. The black is tied into the hots in the switch box and terminates on the top brass screw of the duplex plug. The red is attached to the switch and terminates on the lower brass screw on the plug. Simply put its a duplex receptacle with one plug operating off the switch and one plug hot all the time. This circuit has a 14-2 home run in the switch box and it connects to a single 15A breaker in the panel. My question is if the tab between the two plugs is to not removed will the breaker trip every time the switch is turned on? My initial thought was no this would not happen....the switch would just be rendered useless. I was thinking if we were bumping different phases by using a double pole breaker than it would trip. Am I headed in the right direction?
You are exactly right. If the tab is not removed, the switch won't do anything and the receptacle will be hot all the time. If the receptacle were fed with a multi-wire branch circuit with each half served by a different leg, then the tab would create a 240V dead short.