Hot answers tagged

41

Electricity doesn't care about color. But electricians (both pros and amateurs) do. The color is meant to inform both you and any future worker which wires are hot (usually black or red, but occasionally other colors, such as blue), neutral (white or sometimes grey), ground (bare, green or green/yellow striped). If it is not bare, white or green, it is ...


27

Yikes, good find! This is most definitely the reason. The ground and neutral are only supposed to be tied together at the main panel. In this case, instead of only the neutral carrying current, both the ground and neutral will carry it. There is no legit reason that I know of to do this at an outlet. I wonder if perhaps the neutral was open and the ...


22

There is no reason why they should be reversed. Fix the receptacles and double check all the electrical in your house. It looks like you had someone living there that was comfortable making electrical changes that didn't know anything about electrical.


19

The grounding conductor in an electrical system provides a safe path for fault currents to travel along. It's there to prevent electrocution. No Grounding Conductor Let's say we have a toaster. Inside the toaster are two conductors, a black ungrounded (hot) conductor, and a white grounded (neutral) conductor. To heat the toaster, current flows ...


19

To answer all the issues you raise would require a book on US electrical wiring. Or several. And a copy of the Code. The vast majority of outlets in residences in the US are attached to branch circuits that are rated at 15 Amps and 120 Volts. Current practice and code calls for outlets like these This version is tamperproof, required in many ...


19

The sockets I've been using for the last 15 years have standard screw connection, holes behind that location where the screw pulls a plate against straight stripped wires and the push-in holes. After you've encountered a few burnt sockets from using the push-in connection in the first couple outlets in a daisy chain, you start to realize something. The ...


19

Let me introduce you to the wonderful world of Google Image search: nema 5-15 dimensions It's a great way to find drawings and other visual information. Here's a drawing pulled from the search results: Powercord CN Dimiensions are millimeters with a comma used instead of a decimal point. NEMA Website Following some image searches and regular ...


18

It is difficult to test without a ground reference. One way to do this is with a very sensitive (very high impedance) voltmeter such as a digital voltmeter. Make absolutely sure you are not grounded (and no pets or children are around). Make sure the digital voltmeter is definitely on the voltage setting. Plug one probe into one hole of the outlet, while ...


18

The outlet on the left will accept both 15 amp and 20 and compatible The outlet on the right is a 15 amp only outlet The left is formally a: NEMA R5-20R The right is formally a: NEMA R5-15R The designation is for the pin pattern alone The shape of the 'Square' vs. the 'Double D' outline is cosmetic only The square shape is typically called 'Decora' - ...


17

If wired correctly, this is fine. GFCI outlets typically have line terminals (power input) and load terminals (power to other outlets, which will be protected by the GFCI.) Your contractor will have wired the outlet in the second bathroom to the load terminals of the GFCI in the main bathroom. There should also be a sticker on the outlet stating that it is ...


16

NEMA First let's take a moment to understand what NEMA is, and how it relates to receptacles and cord-and-plug appliances. National Electrical Manufacturers Association (NEMA) is a standards organization, that creates standards for electrical equipment. Each standard has a number associated with it, so you may see something like NEMA 5. That simply ...


15

No. Each type of device serves a distinctly separate protective purpose. Breaker A circuit breaker detects overcurrent faults, it does not detect ground faults. A circuit breaker will stop your house catching fire when the wiring in the walls overheats from prolonged overcurrent, it wont stop you and your family being killed by electrocution. A typical ...


15

That may not be necessary. You may have tripped a circuit breaker or a GFCI device. First see if the breaker to that outlet has been tripped. If the breaker is not already off, turn off the power to that outlet. Confirm there is no power on the case by touching a no-contact tester against it. Carefully remove the cover over the outlet. Again check there ...


14

That is correct. See NEMA 14-50R Source G - Ground W - Neutral X - Hot Y - Hot If you look at the terminal screws on one of these receptacles, you may notice they are different colors. The green tinted screw is ground. The silver screw is neutral. The two brass screws are hot. This is a common pattern in most electrical devices, and can ...


14

You should never chain two GFCI circuits together. When you install a GFCI circuit, you should only ever chain standard outlets off of them. Multiple GFCI on the same circuit can cause each other to trip. So yes, what you want to do is actually what you should do. What you do need to do, however, is make sure you connect the new outlet to the LOAD ...


13

It can be done, but you'll have to swap out the breaker. A "standard" US receptacle is rated for 125 volts, and 15 or 20 amperes. So you'll be going from a 30 ampere double pole breaker, to a 15 or 20 ampere single pole breaker. You could install a 15 or 20 ampere double pole breaker, but since you're not using the second line there's no point. In the ...


12

As I said in the comments to the OP and to Aaron's answer, there are several wiring failures that could cause an NCVT (non-contact voltage tester; usually a pen-looking thing that beeps when you point it at a live electrical wire) to light up, and some that even a plug tester can miss, but that would prevent a "real" load from being plugged in. The first ...


12

Neutrals shouldn't be connected together with the GFCI. Connect the neutral of the line and load to the appropriate connections on each side of the GFCI. Otherwise, the current will appear to go out via the hot connection and not return via the neutral on the load side of the connection, which is exactly the scenario that the GFCI detects and trips on. ...


12

The NEC (NFPA 70 2011 edition) requires GFCI receptacles in kitchens of dwelling units where the receptacles are installed to serve the countertop surfaces. It does not mention a distance requirement in kitchens. The distance requirement of 1.8 meters (6 feet) is for sinks located in areas other than kitchens. Section 210.8 A of NFPA 70 2011 Edition deals ...


12

My experience says to use the rotary tool, but I have always used metal boxes with plaster rings. I have no experience cutting drywall over plastic boxes. I do have three pointers for cutting with a rotary tool: Put as little pressure on the box from the drywall as possible. The more pressure against the drywall, the more likely that you'll get tearout ...


11

All outlets that support convenience plug in items within 8 feet of a water source must be GFI protected. However, the new NEC calls for a separate non GFI circuit (home run) for the fridge or other fixed appliances. These non protected circuits must be single purpose and wired to a single outlet or direct wired and dedicated to the appliance. This can ...


11

A child-proof, or tamper resistant (TR for short) receptacle, has a spring-loaded cover over the electrical contacts that retracts when both pins of the plug press against it. You need to push against both sides simultaneously, and some force is required to open the cover, making it difficult for a child to get something in far enough to get a shock. A ...


11

tl;dr 15 Ampere cord-and-plug appliances can indeed, safely be connected to 20 Ampere receptacles. A deeper understanding NEMA 6 is a design standard for three wire grounded cord-and-plug devices and receptacles. The number after the dash (-), is the current rating of the device. For example. A NEMA 6-20 device, would be a three wire grounded ...


11

The plug specs are the maximum ratings given for how the plug is meant to be used in any given application. So a plug speced as 120V/30A is not designed to be used in applications over 120V and not to be loaded over 30A. Now that said....those numbers do not directly have anything to do with the capabilities of the supply circuit or wiring. If the circuit ...


10

Make sure that your ground is not hot. I found so receptacles in my house that were apparently wired in reverse (according to a receptacle tester). In reality, some had connected the ground for that are to the live wire with no connected to actual ground. As a result, the ground and live are at the same voltage and there's a 120V difference between ground ...


10

The correct answer is that you cannot install a 3 prong grounded outlet without using a 2 conductor with a separate ground conductor, that's three conductors. I know people cheat and put a wire from the ground screw of the outlet to the metal box and hope that the armor case is firmly connected to the box and grounded at the panel. This is not a good ...


10

To answer your first question, no it's not permitted to have a 3 prong receptacle without the ground wire being attached. See some of the other questions explain how you should fix this situation. I believe the short answer is that it should be a 2 prong receptacle (which will be difficult to find and only to be used in grandfathered situations) or you could ...


10

There are two main differences between the outlets shown. First is the left one is a 20 amp outlet and accepts both 15 and 20 amp plugs. You can tell because the left prong is T shaped. The right outlet is 15 amp only because the left prong is just vertical. Second is the visual design: two cropped circles on the left vs. a single rectangle (a.k.a. ...


10

"Switch Loop" is what you're asking about and very common. Mark the white wire with black tape to indicate it's a loop. No codes violated. If that's all you're asking about, then by all means do it. But please don't get creative and use a green wire for hot, blue for neutral and red for ground or something crazy like that. If you search this site for ...


10

Yes, you can. Turn off the power. Add a pigtail from the twist-on wire connector to the top "hot" receptacle terminal. Break the little metal tab between the "hot" terminals on the receptacle. Mark the white wire going to the switch with black tape or marker, so the next person knows it's being used as a "hot". The top outlet should be always hot, while ...



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