What NEMA configuration is this?

[Christoph]

I ran across this receptacle. I understand the horizontal straight blade ones are 250V and the parallel ones are125V is this is a 125V or 250V configuration?

 

[winnie]

Neither. It is a non-nema configuration and likely both 120 and 240V plugs will fit.

Hopefully it doesn't have 240V on it.

Jonathan

 

[garbo]

Have not came across one like this in over 45 years. The few that I have seen were only feed with 120 volts. I have a duplex receptacle in a milk crate filled with new old stock devices in the garage that one halve of the duplex receptacle is 120 volts and the other halve 240 volts. Have separate screws to feed both ends. Have shown it to a few young co-workers and asked them if they were going to use this how would they select a circuit breaker ( s) for it. Some said a single pole for the 120 volt side & a two pole circuit breaker for the 240 volt side. Then told them that would be dangerous to a Johnnie homeowner who decided to work on it without turning off both circuit breakers. Only way I could come up with is to install a three pole circuit breaker but don't think they are approved for a 120 / 240 volt single phase panel. Guess it might be allowed to use a three pole 15 amp circuit breaker if this was feed from a 120 / 208 three phase panel.

 

[kwired]

Those were around before NEMA developed the standards used today.

Though you can buy similar with grounding provisions on Amazon. I think they are sort of common in the grow house industry FWIW. But I still wouldn't want to have those around myself and not knowing or having people not understand some items can't plug into any receptacle that it fits.

 

[CoolWill]

At one time, there was competition between the parallel blades like modern 1-15P plugs and "tandem" blade 2-15P, both for 120 volts. Eventually the 1-15P style won and the 2-15 style went on to be used for 240 V. In the 30s-50s, you might have occasionally ran into either style plug on a 120 V appliance, so manufacturers came up with receptacles that could take both