110/120 V outlet...

[mrcaptainbob]

Why do some outlets have a sideways T shaped neutral opening?

[Speedbump]

I think that's a 230 volt wall receptacle. Used for window air conditioners etc.

[mrcaptainbob]

I doubt that. That neutral side can be used for standard 120V plugs. Seems like that could be confused and burn a lot of appliances. The whole outlet does not have horizontal slots, as would a 230 outlet. It has the standard vertical slots, where the hot is smaller than the neutral. The neutral just has that extra horizontal. Just wondering the why of stuff....

[akaothermick]

20 amp outlet

[HayZee518]

If you look at a 240 volt air conditioner plug you'll see a horizontal leg and one vertical leg. There is no polarity on the plug as in a 120 volt receptacle, one leg has a larger slot to indicate the hot from the neutral leg. Also the amps of a 240 volt receptacle is set at 20 amps. A regular polarized 120 volt outlet can be either 15 or 20 amp.

[hawkins111]

The NEMA 5-20 AP variant has a "horizontal" neutral blade (in a plane that would intersect the hot blade). The receptacle has a T-slot for the neutral blade which accepts either 15 A parallel-blade plugs or 20 A plugs.

[mrcaptainbob]

Thanks for the info, guys. I learned stuff again!!

[Speedy Petey]

The NEMA 5-20 AP variant has a "horizontal" neutral blade (in a plane that would intersect the hot blade). The receptacle has a T-slot for the neutral blade which accepts either 15 A parallel-blade plugs or 20 A plugs.

This.

Both 125V and 250V versions of 20A receptacles are typically T-slot on one side. They are basically identical, with the only difference being which side the T-slot is on.