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 ...


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 ...


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 ...


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 ...


5

No, that's not right. -- Unless UL says it is (i.e. if they approved the labeling and instructions for the lug to say that you can do that). But I really doubt that. Retrofit a ground bar. They are readily available in the $7 range. Your panel probably has holes pre-drilled and pre-tapped for an accessory ground bar; add a photo of your panel's labeling ...


5

Our first rule of subpanels is Think Big. Really Big. A 6-space panel might be dirt cheap and cure the itch today, but for a couple of pizzas, you can get a 30-space and cure the itch forever. We really want you to do that. There are plenty of stupid and useless ways to waste money in electrical work, but the one here is going too small and getting in the ...


5

The steel chassis of a service panel is always grounded. You can identify the neutral bar because it's designed with at least the ability to be isolated from the chassis. Hence the standoffs and fiber guard to prevent bare wires from hitting the chassis. You can identify the ground bar because it is irrevocably bonded to chassis. The screw that the ...


3

Edit From your comments and the progression of added pictures it sounds like this is a 400A (Class 320) meter. The last time I did one I had do the ground/neutral bonding in the meter cabinet, run 4 wires from the meter cabinet to each panel, and all the grounding electrodes (rods, metal piping, ufers) had to be run back to the meter cabinet. It looks like ...


3

I suggest that if you are really concerned about electrical safety, hire a professional to look at your electrical installation. You going around with a tester screwdriver and seeing it light up MEANS NOTHING as these testers are very sensitive and light up at the smallest of signals. Capacitive coupling between wires is enough to make it light up. That ...


3

The pipe only needs to be bonded at 1 place, usually this is at the meter. If it is bonded there the entire system is attached to a grounding bond and would be legal. The gas pipe is bonded to prevent it from becoming electrified by a short. It cannot be used as a grounding electrode but the grounding electrode system needs to be attached someplace after ...


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'...


3

Use a GROUND PIGTAIL. One end of the pigtail, the end with the terminal, goes under the grounding screw in the box. The other end is connected to your other ground wires with a wire nut of the appropriate size.


3

The bigger problem is multi-wire branch circuits Looking at the subpanel, I see 32 "circuits" in use, and I only count 15 neutrals. And pretty much every other hot wire is red. This is, without a doubt, a multi-wire branch circuit or MWBC. Now, these are not a defect if done properly - but they are very vulnerable to being done wrong, and that's when ...


3

On a main panel, you always bond the neutral and ground. Just because it's a PON panel doesn't change that. The reason they don't have it "factory bonded" is because sometimes they get used as a sub-panel. This is becoming the case more often. If the panel is covered by a separate disconnect, which is becoming required, then the main panel gets ...


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

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 ...


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

It may sound funny but it is ok and even required in a way your neutral and ground being on the same bar is fine but look closer and you will see a jumper to ground (the panel is required to be grounded, your grounded and grounding conductors are tied together and then to the case so it is functionally the same on separate bars that are bonded and connected ...


2

If the utility neutral breaks you're up against the ground (i.e earth, dirt, soil, water, rocks) being a relatively terrible conductor as compared to a metal wire, so the various tests involving testing the ground with a heavy load between hot and ground are highly dubious. In the USA, the NEC (our local code, presumably not what applies in Brazil) requires ...


2

You will actually need a second driven rod to be safe with the metal pipe to the house being replaced. NEC 250.66(A) allows for #6 copper. Also, that rod is not fully driven. My jurisdiction requires the rod to be driven the full 8’. If you leave the old galvanized in the ground and it is in contact with earth for 10’, then you would not need the second ...


2

The grounding/GFCI scheme sounds plausible. However, you still have a big problem that the 15A receptacles will be on a 50A breaker. They must be on 15A or 20A breakers. Anything larger and you risk a problem of an appliance fault that doesn't cause a ground fault but results in 2X overcurrent (i.e., 30A or possibly more) never tripping a breaker and instead ...


2

Part 1: Know your loads Unfortunately, I am currently renting, and the homeowner refuses to allow any work to be done. I feel you. Same situation here, except my service is 120V/30A split to two 20A circuits for the whole house. We trip a breaker several times a day. STOP. DOING. THAT. Right now! When a breaker trips, reset it ONCE. If it trips again, ...


2

You can drill and tap more #10-32 ground screw holes into the junction box, if you really want to. That is the conventional size. You can use any thread pitch -32 or finer, and any bolt size #8 or larger. You cannot use sheet metal screws as their pitch is too coarse. Also, you cannot use mounting screws to pinch the ground wire between screw and case. ...


2

There is no difference between plug-on neutral and regular panels; plug-on-neutral is just an alternate way to pick up the neutral instead of a pigtail. As such it has no bearing on the question of neutral-ground bonding. Main panels must be bonded; subpanels must not. Also, you are not required to use the provided bonding screw, and you can run a heavy ...


1

Ezequiel, most electricians do not have earth/ ground resistance meters. For example in the U.S. if you drive 2 each 8 foot rods 6’ apart no measurement is required. A single rod must be below 25 ohms but drive a second rod and who cares. I have a multi point tester and can tell you that I have seen up to 6 each rods driven and the resistance was still in ...


1

Follow the conduit I gather the conduit is metal leaving the main panel. And clearly at some point it transitions to PVC. It's possible to do that at a coupler, but I rather suspect it's at an intermediate junction box. I bet the cable from the garage lands in this intermediate junction box, and the ground wire is tied to the metal box at that point. ...


1

Good news: there is an intersystem bonding terminal that'll fit on your existing GEC The good news for your situation is that Arlington makes a bonding device, the GBB5250, that will fit on a 2/0 grounding electrode conductor. You'll have to cut into the conduit housing the GEC to install it, so that you can gain access to the wire inside. However, the ...


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