3 pole receptacle and single pole feed

[bill1952]

Late in a flooring replacement project receptacles and boxes had to be replaced because of construction damage. What was revealed was these were 120 volt 50 amp circuits and at some point over the last 50+ years a 3 pole receptacle had been installed as a replacement. A Hubbel HBL7379. I'm not able to travel to site so don't know the answers beyond what I stated, but, is using a 3 pole receptacle - presumably 2 of 3 for hot and neutral, and the ground for ground, permitted by the NEC?

 

[wwhitney]

The only applicable NEC code section I'm aware of is 406.4(F), which states (copied from 2017 NEC):

(F) Noninterchangeable Types. Receptacles connected to circuits that have different voltages, frequencies, or types of current (ac or dc) on the same premises shall be of such design that the attachment plugs used on these circuits are not interchangeable.

So as long as the HBL7379s are being used consistently for the same type of circuit, there's no requirement that the use match any particular standard.

Cheers, Wayne

 

[bill1952]

Thank you Wayne. That is very helpful, though a little surprised.