15A Duplex Receptacles on a 20A Circuit - Safe/Acceptable?

[DrDeke]

I often see 20 A circuits connected to multiple 15 A duplex receptacles in houses/apartments, and I am wondering whether this is a safe practice.

Presumably, the idea is that the various loads on the circuit might exceed 15 A in total, but that a single appliance drawing more than 15 A won't be able to be plugged into these receptacles due to the differing blade shape.

What would happen if you plugged two appliances, each of which draws 9 A, into a single duplex receptacle on such a circuit? The total current passing through that receptacle would be 18 A, which would appear to exceed its 15 A rating. Would this be an unsafe condition? Or are "15 A" rated duplex receptacles designed in such a way that they can handle more than 15 A total, as long as each individual "plug" on the receptacle draws no more than 15 A?

 

[Little Bill]

The OP is not an electrician or field related to the electrical industry.
However, I'm allowing the thread since it's just a question in general. So only answer with what pertains to the question.

@DrDeke- 15A receptacles are allowed on a 20A circuit as long as there are more than one receptacle on the circuit.
It is safe because the inside of the receptacles on both 15a & 20A are the same. Only difference is the plug prong that has the extra "T" on the 20A.

 

[infinity]

What he said. ↑

 

[flatlander]

You have no idea how many professionals out there waste money on a 20 amp duplex in a normal residential application.

 

[goldstar]

And, it should be noted that there aren't too many appliances that utilize a 20A plug. The only one I have is my Greenlee PVC heater and my wife doesn't like to cook with that.

 

[roger]

The only one I have is my Greenlee PVC heater and my wife doesn't like to cook with that.

I have actually done that.

Roger

 

[goldstar]

I have actually done that.

Roger

Didn’t have a microwave handy that day?:lol:

 

[DrDeke]

Thanks for the info everyone!

 

[Adamjamma]

As long as the wire is sized for the breaker, and the voltage drop, it does not matter what outlet is used unless the outlet is bigger than the circuit, is what I was taught... in other words, you can build the circuit for 50 amps for a stove but instead only use a 15 amp outlet on it... however, in that case, I might switch the breaker to twenty or less trainer than use a fifty amp breaker...
but, that said, in some cases because of distance you are stuck using an 8 or 10guage wire to feed fifteen amp outlets due to the distance from the panel..
I used to run into that back in the eighties at the old ironworks I was helping to restore.