I may be wrong, but I'm thinking that it's wrong because someone could see the 20a receptacle, and change the breaker to 20a with the wiring being 14 guage.Why wouldn't a 20A receptacle be allowed on a 15A breaker? My understand is that the point would be that the weakest point in the system should be the breaker, and that is the case here.
Another concern is that someone will plug a 20Amp appliance into it and just blow the circuit - over and over and over again.nothing wil happen. What would be a concern is if you have a 15 amp outlet on a 20 amp breaker. What is your concern regarding this condition?
An inexperienced person might do that. The breaker ampacity must match the conductor size and not the outlet. I would hope an electrician would see the conductor at the breaker and make the decision as to what size it should be. If the wire is #12 cu then you can swap the 15 to a 20 amp breaker. However, if in the circuit someone installed #14 cu then there may not be a way to see this if it is inside the wall.I may be wrong, but I'm thinking that it's wrong because someone could see the 20a receptacle, and change the breaker to 20a with the wiring being 14 guage.
this is correct... noting that it is a DUPLEX, you may not have a single 15 amp receptacle on a 20 amp circuit, however, it does not happen the other way around, you may not have any number of 20 amp receptacles on a 15 amp circuit...A 15 amp duplex receptacle is perfectly fine on a 20 amp branch circuit and is code compliant.
As far as the, at this point hypothetical, possibility of plugging a 20 amp load into a 15 amp circuit with a 20 amp receptacle... How many 20 amp loads are there really that would not be able to plug into a 15 amp receptacle? I can't claim to know everything that might get plugged into anything, but frankly I can't think of anything I've seen that uses the 120V 20 amp plug shape.
They are quite rare in a typical home environment though. :laughing:not around motors or shops much huh.
the L shaped 20 amp 120v plug exists for a reason....just because YOU havent seen 20a devices doesnt mean they dont exist.