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38

Neutral is not ground Ground wires are all connected to each other in a big web. That is fine, since grounds do not flow current except during (momentary) fault conditions. Many people think "Oh, neutral wires are the same, whatever". No. Neutral is not ground. Neutral is the normal return current path, and it carries the same current as the hot(...


23

The technique is called double-switching. According to this article, on AC equipment the technique is used to avoid dangerous conditions when hot and neutral are reversed, as often happens with outlets that have been improperly wired. It is permitted by this exception in NEC 404.2(B): 404.2(B) Grounded Conductors. Switches or circuit breakers shall not ...


22

There's a rule to prevent that shock In a multi-wire branch circuit (which shares neutral), Pigtail neutrals. This is why: so you can remove any device for servicing without severing the neutral that other hot wires are depending on. Set aside, for now, the fact that this isn't a MWBC and is, in fact, a disaster. Consider the neutral above the ...


21

No, you cannot do this. Assuming the nearby outlet you want to borrow neutral from is on a different circuit, you will be overloading its neutral. Even if it is the same circuit, it's very bad practice to leave broken wiring energized without fixing it -- what if it moves a little and reconnects just enough to arc? Then your house is on fire. However, ...


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

Power doesn't want to return to earth. It wants to return to source. For natural power, ESD and lightning, yeah, source is earth. However, for human power, source is the transformer or battery. So hot wants to get back to neutral or the other hot. As it happens, there's an equipotential bond to keep the three voltages (240V and neutral in the middle)...


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 ...


18

I found that the neutrals are tied together in this box, is this allowed? Absolutely never. If a box contains 2 different groups of hot wires that do not interact with each other, their neutrals must not interact either. Neutral is the normal return current path, it flows the same amount of current as the hot. You notice we don't put fuses on neutrals. ...


17

Mixed neutrals are when the neutral wires on two different circuits are tied together somewhere. For example, a bedroom can have outlets on one circuit, and ceiling lights on a different circuit. The switch by the door can have a switch for the outlet, and a switch for the light. If the neutrals in that box are connected together, that's a shared neutral.


15

Absolutely not. That sort of thinking works with safety ground, which does not ever carry current, except during a fault condition (and we hope there aren't 2 independent fault conditions occurring at once). However, current flows in loops. Neutral is the normal "return half" of the loop, and it needs to be dedicated to this circuit. In fact, neutrals ...


14

Switches are not circuit breakers (overcurrent protection). They cannot protect wire and do not make it ok to use smaller wire past them. If any 14AWG wire is used, you must downgrade the breaker to 15A, and downgrade the countertop receptacles to 15A. The other wire can remain 12AWG. This will mean it is not one of the two mandatory 20A circuits for ...


14

Probable reason: they made ONE saw assembly and used a motor that could be configured as 110 or 220. For 220 you would break both lines, for 110 you don't need to, but there is nothing saying you can't (so long as your switch breaks both lines together), so it's just easier to have everything the same.


14

No, that's illegal and has always been illegal. You are confusing neutral and ground, which is understandable since they go to the same place in the main panel. However they are actually different and separate; they are tied together in the main panel and that is the only reason they're allowed on the same bus. Don't let that confuse you. The water heater ...


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 ...


11

Considering there is some amount of either wrong, or maybe just misleading, information regarding your broad question which, in turn, can lead to ambiguities and poor and/or dangerous actions, I, a real electrician, will add my hat in the ring backed by the NEC. Because many people may search and find this post, as it is very generally asked, and in a given ...


11

This is actually rather easy to fix The problem is that the light on switch 2 was routed using the hot and neutral from circuit/leg 2, while the switch itself is powered by the hot from circuit 2 but the neutral from circuit 1, creating circulating currents that can heat metal parts and cause EMI as well as a Code violation (300.3(B)/310.10(H)). Moving the ...


10

Based on further conversation.... this is an emergent condition that is trying to kill you. It hasn't succeeded only because the shock path to source is high-impedance and limiting current flow to below 10ma. (if you can feel it, it's at least 1ma). Naturally occurring impedances can change dramatically, so it could turn and kill you tomorrow. You say ...


9

It's using the earth as a return path You really don't want to do that. Dirt doesn't conduct electricity very well. Your neutral is bonded to ground in your main panel. The power company's transformer also bonds neutral to ground at the pole, and all your neighbors have neutral-ground bonds like yours. The current is trying to return to source (neutral)...


9

If you have any #14 wire in the circuit, you have to put a 15 A breaker on it. So, to keep your 20 A breaker, you should use #12 wire everywhere, and run #12 to the switch and lights.


9

Green, yellow-green, or bare are supposed to be safety ground only. In North America, neutral is required to be carried on white or gray wires. If neutral is not needed in a cable, the white can be re-tasked to be a hot wire. Code now requires such white wires be marked with tape, but most installers do not. Hots are every other color. You have 2 white wires ...


9

"Never" is a bit strong. This is not a plain "screw terminal" where that would be true. This is a "screw and clamp" and appears to be designed to correctly hold 2 wires, so you are good. That extra bit of brass between the screw-head and the back plate is what makes the difference, along with the two grooves to hold wires in ...


8

Because the grounding system is a safety system, and is designed to only carry current during a fault. If you use a grounding conductor as a grounded (neutral) conductor, you'll have current flowing on water pipes, faucets, appliance frames, metal electrical enclosures, and anything else that's grounded. Doing this could lead to property damage, injury, ...


8

A GFCI breaker does not know or care what happens upstream (elsewhere in the subpanel or back at the main panel. All that matters is that neutral and hot are connected to it properly so that it can detect the difference between them. If there is a ground wire going to the protected device then that ground must be separate from neutral until sometime past the ...


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 ...


8

You have no ground visible. Hot is switched with Black in and out while Neutral is passed thru.


8

Is this on all your circuits? Are half your circuits under 120V while the other half are over 120V by about the same amount? If so, turn your main breaker off IMMEDIATELY. Call your power company and report an OUTAGE. It actually is a genuine outage. One of the wires from the pole has broken.* It's a 30-minute fix for a power company boom truck, happens ...


8

Generally neutrals for separate hots should be isolated, grounds should always be jointed. The exception to the neutral is a Multi-Wire Branch Circuit. You could have a 3 conductor cable leaving the panel, black/white/red with the black and red sharing a neutral. In a modern installation the circuits would be adjacent with handle ties or a multipole breaker. ...


7

Replace this panel before it burns your house down! You need a new panel not a new neutral bar, as this panel is trying to cook you, your kids, and your house as I speak. The FPE Stab-Loks are rife with trouble, and as you have seen, will attempt to burn your house down instead of doing their job. In particular, at least one of your breakers is out of ...


7

Chase down the matching neutral and remove it. Otherwise it will drive you crazy, and be a loose end of wire unaccounted for. What's more, it could wind up still being in use by some other circuit which shouldn't be there. Part of the reason to fully explore an electrical system is to look for surprises. Besides, since all wires must terminate in ...


7

You'll need to find something that doesn't need a neutral, or run a /3 cable to replace the switch loop Unfortunately, the timer switch you have needs a neutral, which your old-style switch loop wiring does not provide. So, you'll either need to find a different switch that doesn't need a neutral, or to replace the existing cable with a /3 cable so that ...


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