18

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 ...


10

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 ...


5

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


5

You must buy lugs either way. Do it right. You can't double-tap a lug. You can buy "staircase" lugs that are 1-lug width but provide 2 lugs, but you can't torque one without removing the other. And they may not fit on your breaker. In that case, you'd use 3-lug Polaris connectors. Regardless, these don't come in small-large-large, so you'll have ...


4

First, don't use obsolete cable because it may not comply with current Codes. Rule of thumb: If the cable has a ground wire, you have to use it. Only certain types of metal-jacketed cable are allowed to use the jacket as the ground wire. On the types that are not, they include a ground wire. Since you are in all metal boxes, you ground this cable to ...


3

Ground wires were not implemented on a large scale until a few decades ago (possibly after your home was built). Outlets themselves may not have even had ground screws. You should definitely add pigtails to the existing connection and ground your outlets. Use the same size wire as the existing ground conductor (or slightly larger if that's what you have on ...


3

That ground bar The proper way is neutrals on the neutral bar, and grounds on the ground bar, and a neutral-ground bond. I'm a big fan of using a wire for that, because a) it makes burnout much more obvious (a screw head can hide a vaporized screw shaft), and b) you can put a clamp ammeter on it, which will reveal any ground leakage (ground faults). Very ...


3

Ground bar fun and games The original installer's decision to fit a separate ground bar for the ground wires was a good one from a neatness standpoint, even though Code does not take issue with having all the grounds and neutrals on one bar at the main panel, as that's the only place where neutral and ground connect (via that bonding strap you see bottom ...


3

One bond. That's already in your meter/disconnect. Everything else is a subpanel, ground & neutral separated. Slightly debatable whether the main disconnect nearby trumps the "six motions of the hand" to shut everything off rule for this panel, sometimes interpreted as 6 breakers. Wait, you were planning to take off ahead of the main disconnect? No, don'...


2

When adding a branch circuit, you would never, ever have cause to add any neutral-ground bond anywhere. That should only be done as part of a total review and reassessment of your Grounding Electrode System (the network of bare/green wires from your ground bar out to your branches and appliances) and your Equipment Grounding Conductor system (the hefty ...


2

Be clear: electricity wants to return to source, not ground. Human-made electricity wants to return to the supply transformer, generator, or solar panel which made that electricity. Grasping this concept will make electricity make a lot more sense. Nature-made electricity (lightning and ESD) wants to return to its source, which is typically earth. ...


2

Yes and No. There are two separate systems with "ground wires" in the typical US residential service, the three wire Edison service. The Grounding Electrode System (GES) consists of ground rods and other grounding electrodes, connected (bonded) by a grounding electrode conductor (GEC) to the neutral at the first means of disconnect. The Equiment ...


2

You see on the old receptacle, where there is a little cardboard donut and a bunch of wallpaper and junk stuck to the receptacle yoke? That. That is a picture postcard example of not an acceptable grounding path for receptacles. Those things are insulators, and will prevent solid contact between the yoke and the metal box. Also, the yoke is catching the ...


2

The ground screws do not make contact with the box. They're intended to secure a pigtail from the ground wire bundle (or a passthrough loop). On modern outlets they'll be green. Some outlets are self-grounding. They have small tabs or wire springs behind the screw mount ears that make a positive connection. You can either replace your outlets with self-...


2

You need to bond the subpanel ground bus to the plumbing You will need to run a bonding conductor from the subpanel ground bus to a grounding clamp on the plumbing, as per NEC 250.104(A)(3): (3) Multiple Buildings or Structures Supplied by a Feeder(s) or Branch Circuit(s). The metal water piping system(s) installed in or attached to a building or ...


2

All your pumps should have the #8 connected to them (bonding), as they can become energized and you don't want that using your pool for a ground. This is not a substitute for grounding the pump through the electrical wiring. You need both, per NEC 680.26 (a) Double-Insulated Water Pump Motors. Where a double-insulated water-pump motor is installed, a ...


2

Your ground path is through the EMT conduit. It needs a proper connection to the main panel ground and to the sub panel ground. You could use grounding bushings, but standard EMT connectors meet code. The “connections” to the concrete reinforcing are not part of a normal grounding or bonding approach. This kind of bond is only used at the service entrance ...


2

Yes, it's allowable to tie a ground wire to a junction box and let the metal conduit carry it the rest of the way back. However, if the ground wire is already in the pipe, I'd leave it in there - belt and suspenders - unless you need the conduit fill. You terminate a ground wire at a junction box by attaching it to a ground screw. Virtually all junction ...


2

Two different problems, two different solutions, but only one circuit from the pole to the house Your problem here is that you are trying to solve two different problems (the porch circuit and the well pump) in the same, incorrect way. As it turns out, since the porch is attached to the trailer (and thus part of the same structure), you cannot do what you ...


2

At minimum you need a rod (or more usually 2, more than 8 feet part, since that gets you out of measuring the resistance cheaper than doing the measurement) at the entrance and the same at the mobile home. Given it's not a huge expense, buy 6 and sink a pair at the pedestal as well to be sure. No points off for doing more than the minimum. I have 5 or 6 and ...


1

Depends. There are several methods. Run a ground wire Obviously. Direct contact Note that receptacles have a metal yoke that hold the mounting screws. This yoke typically has "drywall ears" to hold the socket even with the drywall surface. If all these are true: The junction box is metal, and grounded The receptacle's yoke, when screwed down, has ...


1

You always have to run a ground ~. Rods will never do. You must, must, must, in every case run a ground ~ from the main to the subpanel. Doesn't matter if you're running it 3 feet, to an outbuilding or up a space elevator. You have to run a ground ~ or you are out of Code. PERIOD. Wait. Shouldn't ~ be the word "wire"? Not quite. With rare exception, ...


1

Leave the ground rods. Install a second set at the new service location. The IBT only needs to go to ground rods. It doesn't need to go to particular ones. This plan depends on there being a ground wire between the old and new rods; it's a rare time when metal conduit shell, water pipe, etc. won't do. There is no penalty for more ground rods than ...


1

Nothing in 250.94 is intended to prohibit multiple IBT bars, so get another one and toss it on the same conductor the first one is attached to The concept behind the presence of 250.94 in the NEC and its requirement for an intersystem bonding termination (IBT) is to provide installers of auxiliary systems (such as telecom, antennas, alarms, and such) a ...


1

Run a new feeder in metal conduit If you're going to run a conduit from the main panel to the subpanel, I would simply run a 2" EMT and pull an entirely new 100A feeder (1AWG Al hot/hot/neutral with the EMT for a ground) through it in your situation. This is because the existing feeder SE(?) cable seems to have been improperly installed to begin with (its ...


1

Back in the old days, grounds didn't exist at all. Mains electrical was wired as an isolated system. It still is, but now we've added ground as a safety shield. When they started to require grounding, they went to pains to make sure they weren't mandating old work be retrofitted. Old work is "grandfathered" - if it was legal at time of installation, it ...


1

You need a ground wire and ground rods at both structures You are correct that you only bond neutral to ground at the service entrance. However, current Code not only calls for a grounding wire between the structures (which you have provided), but for a grounding electrode system at both buildings. This can be a concrete-encased electrode (if provided), ...


1

You will need a ground wire running back to the house. Since you have upsized the wire beyond bare minimum, a fudge factor gets applied to the required grounding wire size, so the required size is #6Cu or #4Al. If it is aluminum, it must be in an insulated jacket; copper can be bare. The ground rod is not enough. You always need the ground wire back to ...


1

The gas system only needs to be bonded at one point Bonding the black iron at the meter to a legal bonding point (anywhere on the grounding electrode system, basically, using a listed tap connector such as an ILSCO GTT-2-2 to connect the gas bond wire to the GEC, or simply by landing the gas bond wire on the intersystem bonding termination device if one is ...


1

You probably don't need to go full RMC; cheaper EMT and plain stamped handy-boxes will do. Both types of conduit are acceptable as grounding paths for 200A++ of fault current, your milliamps of signal noise will be handled with ease. I never run ground wires inside EMT. If you have a section of Conduit isolated from mains grounding, grounding it is ...


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