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Many AHJs will accept this if there are no 240V circuits in the house. 406.3(F) requires that receptacles connected to different voltages, frequency, AC or DC, be of non-interchangeable design, but does not specify anything further.
We have a similar situation in Britain, where it's not uncommon to find the old BS546 round-pin 2- and 5-amp (250V) plugs being used for 12 or 24V D.C. power.

I was sure that our older "code" editions contained a similar clause about not using the same type of connectors for different voltages or systems within the same installation, but I can't seem to find it at the moment. Maybe I'm getting confused with the American NEC.