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 ...


25

I do a lot of work on older homes and see stuff like this all the time. Keep in mind that the equipment grounding conductor (EGC), that bare safety ground, was not always present in wiring systems. If you see old homes - a little older than this one - with two-prong receptacles, those were wired back before the EGC was part of the system. I think when ...


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 ...


18

Whoever wired this panel simply was not paying attention The installer who wired this panel did not pay attention to the schematic on the label, assuming that removing the bonding strap was enough here. However, the split ground design of these Murray panels means that the left-hand bar is factory bonded to the case, with the right-hand bar being the only ...


13

I'd be seriously tempted to email that picture to the licensing board... I assume from your question that this was installed, incorrectly, by licensed electricians. Buy a ground bar to fit your panel, note the pre-threaded holes in the back of the panel for the ground bar, move the ground wire to it, and remove the bonding screw. Or call up your "...


12

Conduit (RMC, IMC or EMT) is an NEC-accepted ground path. So, if the wires are in steel conduit, no OTHER ground wire is required. If that gives you concerns, you might find this link reporting research into the effectiveness of conduit as a ground relieves them. Updated link to NEMA Technical Services Department Bulletin 97.


12

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 ...


8

If you're in an area that has adopted National Electrical Code, you'll have to run a 4 wire feeder. You'll also still need the ground rods at the shed, which you'll bond the grounding bar in the panel to. If it's an existing 3 wire feeder, and there are no other conductive paths between the buildings. Then yes, you'd bond the grounded (neutral) bar. However, ...


8

National Electrical Code does allow metallic conduit and tubing to be used as an equipment grounding conductor, as long as it's installed properly. However, before using it as such in an existing installation, you should verify that it provides an adequate continuous path to ground. National Electrical Code 2014 Chapter 3 Wiring Methods Article 342 ...


8

understand the logic behind Bonding the Neutral and Isolating Ground the green earth ground or bare copper always connects to the metal of the panel box, or any metal that you touch. the [white] neutral only connects [bonds] to the green earth ground connection at the main panel. in any sub panels wired from the main panel you isolate the neutral from ...


7

Sounds like you have an improperly bonded neutral somewhere. If it isn't easily identified at the main service panel, you'll want to do a couple of things: Call your electrical company and request (or if necessary demand) that they check to make sure the incoming neutral wire is grounded correctly on their side of the service. Make sure that the water ...


7

It sounds like this is what you're describing... If this is indeed what you've encountered, you should remove the grounding conductor from the twist-on wire connector used to connect the white wires. The only place grounded (neutral) conductors and grounding conductors should be bonded (connected), is at the main service disconnect. If there are no ...


7

It turns out that between the 2011 NEC (which Tester101 cited) and the 2014 NEC -- the answer to this question changed! Under current (2014) code -- a new point 4 was added under 250.130(C): (4) An equipment grounding conductor that is part of another branch circuit that originates from the enclosure where the branch circuit for the receptacle or ...


7

Here is what the National Electrical Code says: 250.64 Grounding Electrode Conductor Installation. Grounding electrode conductors at the service, at each building or structure where supplied by a feeder(s) or branch circuit(s), or at a separately derived system shall be installed as specified in 250.64(A) through (F). (C) Continuous. Except as provided in ...


7

Your feeder appears to be in metal conduit, which is the grounding conductor Since your feeder appears to have been run as wires in a metal conduit, that conduit would serve as your grounding conductor provided it is continuous back to the main panel. I would turn off the feeder at the main panel and do a continuity check from the neutral lug on the panel ...


7

It's bonded, alright Meter-main boxes like yours have their neutral bars permanently bonded to the case at the factory, and thus have a notation on their label saying that they are "suitable only for use as service equipment" (emphasis mine). In your case, this is done through the mounting of the left-hand bar; if you look closely at it, you'll ...


7

You are correct--the panel should not be bonded. Most panels will come with a bonding screw in case it is being used as a main panel and first means of disconnect, which yours isn't. When you install your sub panel, all neutrals from circuits in the panel need to be attached to the neutral bus and a second grounding bus needs to be installed in the sub panel ...


7

Yes, pull the jumper and move the grounding wires You have a classic "service disconnect outside, panel inside" configuration, and with that, the inside panel is a subpanel. So, you'll need to pull the bonding screw and jumper from the neutral bar and move the grounding wires to the grounding bus in the panel. Note that a grounding electrode ...


6

The new 30A panel needs a 4-wire feeder from the 60A panel. This is two hots, a neutral and an equipment ground. The remote 30A panel also needs a grounding electrode (or two) since it is in a detached structure. This grounding electrode has NOTHING to do with the equipment ground run with the feeders. The two serve very different purposes. In the ...


6

Metallic Boxes If it's a metal box, technically, the grounding conductor should be connected to it (NEC 2011 250.148(C)). However, if you've already installed the fixture without bonding it, it's not likely to cause a problem. If the fixture itself is properly grounded, and the canopy completely covers the box. It's not likely anybody will ever come into ...


6

The bare copper wire and any green insulated wires are meant to be connected together, making it a "party of three" as you stated in your question. That said there is another consideration to take into account as well. These safety ground wires are also meant to be connected to a common ground point of the electrical box as well. If one of these wires (...


6

Look for the Pal nut on the other end holding the ballast to the metal housing it's mounted on. It's made to bite through the paint to ground the ballast to the housing which is then grounded. For safety, it's more important that the metal housing you will touch be solidly grounded than the ballast which is inside and protected from direct contact be ...


6

My guess would be that because the fixture has a metal frame, the ballast is grounded via its contact with frame. If the frame were plastic, you would need to use the terminal on the ballast. If you're converting it to hardwired, you should definitely connect the ground wire to the grounding screw. You're also going to need to cut a hole if there's no ...


6

First off, why is the ground #6? Seems big unless the circuit is over 60A. Personally, as Tester commented, I'd use a double lug screwed to the box via a machine thread screw, that is if you can find one small enough. The one Tester linked is quite large for the application. Smaller ones might be hard to find though. This one is the smallest I could find: ...


6

Because your water heater has dielectric unions, so the hot and cold plumbing are isolated from each other. Bonding the plumbing, attempts to keep the hot and cold plumbing at the same electrical potential. If this bond is not in place, it's possible for the hot and cold plumbing to be at different voltage potentials. Which means if you grab a hot and ...


6

Grounding Electrode System You're going to have to install a grounding electrode system. This is typically done by driving two ground rods spaced at least 6' apart, and connecting the rods together using a properly sized bonding jumper. Then you'll install a properly sized grounding electrode conductor, from one of the ground rods back to the main grounding ...


6

The tester will show "correct". Opening the outlet is the only way to check it that I know of.


6

Good choice on the antenna. Lots of high quality reception for free. In fact, OTA (over the air) TV signals are often of better digital quality than TV through cable distribution. Cable TV is compressed/decompressed one more stage, to reduce the digital data rate, squeeze more channels, and make more money. And OTA latency is lower: you will cheer for a goal ...


6

That would be a code violation. You may not re-mark green, green-yellow, or bare to any other color, and you may not re-mark non-ground colors to ground colors.


6

OK, let's talk about the electrical system's Grounding Electrode System first off. Out at the pole -- and this is not in our jurisdiction (NEC), it is in the power company's codebook (NESC): the pole-top transformer has its neutral wire grounded to a pole-side grounding rod. That is what makes it "neutral". In NEC territory now, we receive power ...


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