A 20 amp receptacle usaully is a bit stronger, but the reason for the T is that devices such as large portable heaters, air conditioners, and even air compressors will have a T shaped plug on them that will ONLY go into a 20 amp receptacle. This keeps you from plugging into a 15 amp receptacle. 20 Amp White Decora T-Slot Receptacle Item: # 3665-046 Model: # 6352W-BU; Order Online. FREE SHIPPING to a store near you. Add To Cart Save To List. I didnt know either so i had to research. 20A Outlets: Some electrical outlets have a 'T' shaped slot on the neutral instead of just a vertical slot. These outlets are rated for 20A, and can receive special plugs (with a sideways neutral prong) for appliances which draw more than 15A. The NEMA 5-20R (T-Slot) is a 3 wire grounded connector rated up to 125VAC and 20A. The 5-20R T-Slot receptacles are often used when 20A circuits are installed due to flexibility of being downward compatible with the 5-15P. The Receptacles are the defacto power supply for all of North America.

Officially it is a NEMA 5–20R receptacle. The plugs it takes don’t actually have “T”-shaped contacts.

Hey all,

Just wanted to do a quick post about these “t-shaped neutral” outlets. They are important to know about and you should keep an eye out for these on location shoots (I did not know the significance until just the other day, whoops!).

When you look at a typical household outlet (called the Edison 5-15), you’ll see this:

This particular receptacle is rated for 15amps at 115volts. Most households have a couple of 20A circuits located in the more power-hungry sections(kitchen, bathroom, laundry room, etc).

I recently had the pleasure of learning first hand what can happen to the hubbell(male/female connectors located at end of a stinger) and the receptacle itself when it’s overloaded (it gets charred and breaks and it smells like ass!). As a 2K tungsten fixture draws 17.4A, you are putting strain on your 15A receptacle (as seen above), even if it is on a 20A circuit.

This is the “t-shaped neutral” 20A receptacle(called the Edison 5-20):

When you have an Edison outlet you can have two different kinds of straight connectors, polarized and non-polarized (for the most part you will see 3 different types of outlets, the two I have pictured here and then one of the much older receptacles that has no ground/is non-polarized). The non-polarized outlet has the neutral and the hot (the two straight connectors) being the same size whereas in the polarized version, the neutral is the visibly larger straight connector(the hot is smaller). The reason why its called a “t-shaped neutral” is because, as you can see in the photo above, the neutral is the larger of the two inputs and it has a slot sticking out of it that shapes it into a T. This makes it easy to spot when you are on a location/tech scout. It’s important to note where or if you have these because they can handle the 2K’s load without melting.

T Slot Receptacle Switch

“T-shaped neutrals” are mostly used for commercial floor buffers, vacuums and such, which is why they are typically found in commercial buildings.

There is a lot more info out there about these kinds of small yet important things and if you want to know more, send us an email at gaffersuniteinfo@gmail.com.

5-20r T-slot Receptacle

Cheers!

T Slot Duplex Receptacle

Peter Mosiman