Legend: 🌞‼️ 🔨 🔥📜
Common Types of Outlets in the United States
Electrical standards and requirements vary country to country. This post is specific to power in the United States and Canada; if your outlets don’t look like the ones shown below, this post is not applicable to you.
The commonly-found electricity in the United States – when you’re talking about regular electrical outlets that you use to plug in lamps, or your laptop, or – oh, most things that aren’t major appliances – is 110 volt, alternating current. Outlets/receptacles are considered “female,” and plugs are “male”, for somewhat-obvious reasons.
In order to be up to code in the United States, electrical outlets must be grounded. What does this mean?
Before 1980, almost all electrical outlets in the United States were non-grounded, non-polarized. They looked like this, but are not considered safe today and are found only in old homes.
The technical term for this type of outlet is the USA Non-Polarized NEMA 1-15 2 Pin – 10 Amp outlet (female) and plug (male).
The next piece was the non-grounded, polarized outlet:
This is the USA Polarized NEMA 1-15 2 Pin – 10 Amp outlet and plug.
After the introduction of the polarized outlet came the grounded, polarized outlet:
This is the USA Polarized NEMA 5-15 3 Pin – 15 Amp outlet and plug. The “hot” lead (black wire) connects to the shorter of the two vertical slots, and is either connected by a copper screw, or inserted into a hole. The white (neutral) wire connects to the longer of the two vertical slots, and is either by a silver screw, or inserted into a hole. And finally, the green or copper wire (ground) connects to the u-shaped piece, and is attached by a green screw.
The USA Polarized NEMA 5-20 3 Pin – 20 Amp outlet and plug are rated for 20 Amps of power. It looks like this:
Note that one of the flat pieces is horizontal, rather than vertical. Sometimes, the receptacle is built to handle either a 15-amp or a 20-amp plug. Those look like the image on the right:
📜 🔥 Note that the more current a circuit carries, the thicker the wire has to be to avoid excessive heat discharge from the wire that can result in fire. Consult your local building codes to determine whether the wire in your outlet can support 20A current before attempting to install a NEMA 5-20 outlet.
Ground Fault Circuit Interrupt (GFCI) Outlets 📜
GFCI outlets are a special type of outlet that are required near sources of water, and possibly in other places in your home. These special outlets contain a fast circuit breaker that will cut off the electricity to the outlet at once should the ground on the outlet fail, e.g. if something plugged into it is dropped into water. You should consult local building codes to determine whether you need to install a GFCI outlet.
GFCI outlets look like this:
Not all of the buttons are red/black; some are the same color as the outlet. The red (top) button is for testing, and the black (bottom) one is for resetting the GFCI outlet. They are wired just like any other NEMA 5-15 or NEMA 5-20 outlet.
When To Replace an Outlet 🏠
Renters should contact their landlord to have an outlet replaced. Attempting to do it yourself may be a violation of your lease.
You should replace an outlet if:
- Any part of the plastic cover on the outlet itself (not the faceplate, the outlet) is broken or missing.
- Any black marks are visible around the outlet holes. This means that the outlet or something plugged into it has short-circuited.
- The outlet is non-grounded.
- NOTE: There may not be a ground wire in the workbox in this case. If not, consult an electrician. 💼
- The outlet is not GFCI and is within six feet of a water source.
- A plug falls out or hangs loosely when plugged into it. This happens with old or worn outlets.
How To Replace an Outlet
🌞 DO NOT do this if there is an electrical storm in progress.
‼️Always, ALWAYS turn off the circuit breaker BEFORE you remove the outlet cover. Failure to do so could result in electrical shock.
- 🔨Have your tools ready. You will need the new outlet, an outlet tester, and a screwdriver.
- Remove the outlet cover (face plate).
- Unscrew the two screws holding the outlet to the work box (the box behind the outlet that it and its wires reside in).
- Gently pull the outlet out of the work box.
- Take a look at the wiring. You should see three of them, a black one, a white one, and one that is either green or bare copper.
- Black is your “hot” wire and should be wrapped around the screw marked “hot”.
- White is your neutral wire, and should be wrapped around the screw marked “neutral”.
- The bare or green wire is your ground wire, and will usually be affixed to the screw on the corner of the outlet.
- Working one wire at a time, move the wires from the old outlet to the new one, wrapping the wire around the screw and screwing it down.
- 💡This is easier to do if the wire is wound around the screw clockwise.
- ⚠️ Double check to ensure that you have the hot / neutral orientation correct. If this is wrong when you power the outlet, it can burn out the outlet, ruining it.
- (Optional step) Some people like to wrap the screws with electrical tape to ensure no short-circuits have occurred. Do this only with electrical tape, not with any other kind.
- Gently push the outlet back into the work box.
- Screw the outlet to the work box.
- Replace the face plate.
- Turn the circuit breaker back on, and plug the outlet tester into it. Do not use anything else to test an outlet unless you don’t like it, because any errors in the wiring can fry your test object.