Enquiring minds need to know so the answer I got from the Mike Holt electrical forum is no, this is not allowable.
Mike Holt forum A 30 amp receptacle requires min. 30 amp (#10) wire and a 30 amp breaker.
ScottG wrote:
enblethen wrote:
The amperage would be what the circuit is protected for. You would need to identify the circuit at the service panel to make that determination.
No, the amperage would not be the problem.
ScottG:
Would you provide your code reference?
It's buried in the NEC book and was something I stumbled upon when looking up something else. I don't know the Code number off the top of my head but the second item I wrote about (15A outlet on 20A circuit) is covered on table 210.21. I've found this latter condition to be very common.
I've looked for that 15/30A thing and can't find it easily.
So disregard if you want.