The point I was struggling to make was that by allowing 15A receptacles on a 20A circuit, you couldn’t possibly expect to have any control over whether the user will connect a 12A or 16A load.
What makes this no 'real big deal' is the fact that if you take apart a 15 and 20 amp duplex of the same grade and maker you will find the internal parts are interchangeable.
The only difference between the same grade and make of 15 & 20 amp duplex receptacles is the plastic face plate.
Keep in mind UL requires 15 amp duplex's to be able to handle 20 amp feed thru.
The fact the NEC even tries to control the load that may be plugged into a receptacle is just plain ridiculous.
Bob Badger Construction & Maintenance Electrician Massachusetts
