67

This is because removing a device isn't allowed to interrupt grounding connections Removing a wiring device from the circuit cannot break grounding connections, or else you are violating NEC 250.148(B): (B) Grounding Continuity. The arrangement of grounding connections shall be such that the disconnection or the removal of a receptacle, luminaire, or ...


59

To me it sounds like the conduit was used as the grounding conductor, as allowed by code, and it rusted through, therefore it works when the ground is wet and you have a ground connection through the soil and water. If this is the case, then an additional electrode at the garage probably won’t help as the pipe is in the ground. Your electrician wanting to ...


33

When or is it NEC code compliant to upgrade a 2-wire circuit, by adding a third prong equipment ground from a nearby galvanized cold water pipe? Never! Article 250.118 of the National Electrical Code lists the approved methods of equipment grounding. Water piping systems are NOT listed there. Metal piping systems within buildings are required to be bonded ...


26

That recep appears to be right next to your service panel, connected to the panel by a 1" conduit nipple. That makes it the "magic electrician's outlet". It's not required by Code. It's just a "common practice" for an electrician to fit such an outlet, and place it on a dedicated circuit breaker. This costs about $10 normally ($5 for the breaker, $1 for ...


25

Your house is wired using the EMT conduit wiring method. Individual wires are carried inside metal conduit. The conduit is the ground path. Most commercial and industrial buildings look exactly like this. Since they are individual wires, they are able to use any of 11 wire colors to disambiguate circuits, instead of the usual black white red. If you ...


23

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 into the ...


23

I am glad you are finding it convenient that some devices allow themselves to also be used as splice blocks. However, that is prohibited for certain types of wires: Any and all ground wires Neutral wires on multi-wire branch circuits That is because it will cause serious problems for other (e.g. downline) loads if those connections are severed due to ...


22

Yeah, the root problem is, you see they are both tied together in the panel, but you don't know what that thing is... or you don't even realize that is a thing. Its name is the Neutral-Ground Equipotential Bond. Since we don't know what it is, let's get rid of it. SNIP! Life without an Equipotential Bond Now, your 2 hots are 240V apart, and neutral ...


20

Just some sand paper will be fine. You don't want to use a chemical stripper as it may interact poorly with the copper.


20

The tester can't tell the difference. One way to look at is that electrically, since neutral and ground are already bonded at one location (normally the main panel), the electrons don't know the difference. But the other way to think about it is to look at what the tester is actually doing. What do the Lights Indicate? These testers are actually 3 simple ...


20

The orange colored outlets are installed for an isolated ground. They are electrically the same as regular outlets, except they're built better and the yoke of the outlet is not tied to the grounding screw of the outlet. I've only seen them used with metal conduit and the circuit has its own dedicated insulated ground which goes back to the original ground ...


20

An outbuilding needs two kinds of grounds Electricity wants to get back to source, not ground. Source is the supply transformer, or in the case of natural electricity (lightning, ESD), then yeah, it's earth. The grounding rod is designed to handle natural electricity. Note that natural electricity has VERY high voltage compared to the amperage. The ground ...


19

Green wire is perfectly legit. If you are really lazy or in a hurry you can even get pre-cut pre-stripped green grounding pigtails ready to go. Ground is the only thing it can be used for, but "green or bare" is fine for ground nearly everywhere (I think there are some hot tub/pool specific cases where green is required and bare is not OK, but I ...


18

I think the power guy's assessment was spot-on He said it appeared that the buried cable coming in from the street had degraded or been damaged and that the "hot must have nipped the neutral." What was happening is that the incoming hot probably contacted the ground indirectly via the insulation failing in some fashion. Your neutral bonds with the ground ...


17

No -- that bond wire could save your life! It is very important that all non-current-carrying metal, including the cold and hot water pipes, be bonded to the electrical system ground. This prevents highly unpleasant surprises should a wire in the dishwasher come loose and contact a water pipe! Furthermore, this requirement is enshrined in 250.104(A) of ...


17

Filipino electrical service is a morass. There is some Euro 230V single leg service, and there is some American style 120/240 split phase service. And if those services are wired to Euro or USA standard, they'll be as safe. However, in actual practice, weird things get done in the Philippines. And there is a high rate of electrocutions. This is one ...


17

Someone forgot a fitting Normally, armored cables (like yours) are brought into a box using a fitting designed to clamp the the cable armor, grounding it to the box and also providing a strain relief for the cable inside. Your furnace installer didn't have that fitting on hand, though, so they simply shoved the cable through the hole and shoved a "redhead" ...


17

That looks like a plastic box to me. If it is metal, code requires that the box be grounded. If all the external parts of the smoke detector are plastic then a ground is not required (the same is true with light fixtures). I don’t usually cap bare grounds. I just tuck them in the box (the entire length is conductive, so I don’t see the point). If it makes ...


16

It's called a bootlegged ground. This is commonly done in older houses that had a two prong receptacle and was updated to a three prong receptacle. The old house didn't have a ground and this tricks the inspector's electric checker, so your house passes inspection.


14

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 ...


14

In addition to what @ThreePhaseEel said, the purpose of having two screws on each side is not so that receptacles can be wired in series. While that is allowed, the purpose is for "split receptacle" setups, where only one outlet is controlled by a switch (or each is controlled by a separate switch). This is done by breaking the metal tab that joins the two ...


13

DO NOT connect the ground wire to the grounded (neutral) conductor, as this could lead to current flowing through the body of the dryer (and potentially through you). The installation guide for the dryer will have wiring instructions for both 3, and 4 wire configurations. Check the manufacturers documentation for proper wiring, but I would say the first ...


12

Depends what you're trying to protect. If your goal is to protect the oven from ESD (static electricity) damage or lightning-strike damage, or help it receive radio signals, then going out to a ground spike can help you with that. It won't do a thing for human safety, though. To protect humans from electric shocks, you can go one of two ways. GFCI ...


12

The bare copper wires are the ground (grounds are either green or bare wires). You need to add the green wire from the dimmer to this bundle in the wirenut. The white wires are probably the neutral, providing a return from the lamp to your electrical panel. If you had a smart switch that needed a neutral connection, you would connect there. Note: this ...


11

The neutral and ground MUST NOT be bonded at a sub-panel. They should only be bonded at the main service panel. If you bond them anywhere other than the main service, the neutral return current now has multiple paths, including though your ground wire. You should be able to buy a second bar for the sub-panel if it really is meant to be used as a sub-...


11

The accepted answer states "it's not permitted to have a 3 prong receptacle without the ground wire being attached." This is incorrect. 406.4(d)2(b) A non-grounding type receptacle(s) shall be permitted to be replaced with a ground fault circuit interrupter type of receptacle(s). These receptacles shall be marked "No Equipment Ground". ...


11

In all my years I have never seen a device ground screw rated for two conductors. Even clamp type ground connectors found on GFI devices are only rated for one conductor. You will need to pigtail a single wire to the device. This can be achieved several ways. A green wire nut, a ground crimp, or a standard wire nut are examples.


11

Yes, it will misread. Because magic-8-ball testers are built for one thing: a quick pass/fail test for brand new wiring you just installed. Obviously, in new wiring, you don't have a bunch of the kinds of problems you have in old wiring, like people bootlegging ground off neutral. The device is simply not made to solve those problems. So if you misuse ...


10

That explanation doesn't really make any sense to me personally. The neutral bus bar in your main panel should be bonded to the ground bus bar so in effect, all neutral wires in your house are grounded. The third prong in a typical three prong outlet is known as the equipment ground. This is a safety feature that should cause your breaker to trip if an ...


10

The instructions for the fixture are only correct for a metal box. If a metal box was used, the box itself would (should) be grounded. The bracket that holds the light would then be connected to the box, which would make the bracket grounded. Finally the ground wire from the fixture would attach to the bracket, grounding the fixture. In the case of a ...


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