26

What could possibly go wrong? If the ground wire is bare copper, you massively increased the risk of a ground fault, which can kill somebody or burn the house down. If the ground wire has a smaller cross-section, it will not be protected by the breaker from overheating and can burn the house down. Somebody working on the system may falsely believe the ...


15

You have ground being used as neutral. That is a serious code violation and can cause a number of dangerous problems. In the old days, the only real solution would be to run a new cable. Fortunately, today we have smart switches to the rescue! Look for a smart switch that has 3-way operation but that only needs one traveler between the switches. That can be ...


12

This is not allowed because it violates the rule that in any cable there must be two conductors carrying equal current in opposite directions so the magnetic fields cancel. That T- T Loop top right would have one traveler carrying current, no current in the other, and no neutral present carrying current in the opposite direction. The time varying magnetic ...


10

I'm assuming by drain, you mean neutral. Ground wires can not be used as any other conductor, repurposed. If its green insulated or bare copper, then it must be used as a ground and only as a ground.


9

This is safe as long as the black, red-black, and white-black wires between the switch boxes are all in a single conduit or cable. That is, the switched-hot and the two travelers must be physically adjacent outside a junction box. Same is true for the neutral and hot from the panel to the old switch box, and for the neutral and switched-hot between the old ...


7

You can't - without some active component or spare poles on the switches. If you have spare poles on your switches, simply connect all three switches in parallel and to the 4. light. If you don't, you'll have to either change switches, or install a relay in parallel with each of the three light bulbs, and connect the output of those relays in parallel to ...


6

You're fine -- having neutral in one of the switch boxes is sufficient While the text of NEC 404.2(C) isn't the clearest on this, in most multi-way switching situations, you can get away with only having neutral available at one switch box. This is because 3-way smart switches either use a mechanical remote switch that only needs a couple of wires run to it,...


5

This is two three-way switches from the looks of things, but wired in a nonstandard fashion From the wires you have, this does appear to be a fairly basic three-way switch circuit with both switches on loops from the light fixture, but with the way the second switch is wired, and the way you were able to get it working, it's not a standard three-way switch. ...


5

Based on your details on what you did with the replacement outlet, I'd say you didn't remove the metal tab on the outlet connecting the two brass, power, screws. Doing this allows the two outlets to be split between always hot and switched hot. The one wire you "punched" into the backstab should be pigtailed so you don't use the backstab. they are ...


5

OK, I notice that in the "junction" box, you have matched up all black wires and all white wires. As if you expected that all wires just come naturally color-coded like that. No, that does not happen, unless you do it yourself. Designing a 3-way+lamp complex is not that hard. Certain wires have to go certain places, and they have conventional ...


5

Don't waste your time. Have a /3 cable bypass the lamps. This is a rather straightforward problem if you aren't trying to snake the travelers through the bulb sockets. I know you imagine some great cost savings in wire by doing that... forget it. Besides... running travelers through the bulb sockets is pointless, and takes up a LOT of splice space inside ...


5

No, you're actually fine on that front here The C-D conduit meets 300.3(B) despite not having a neutral in it for the same reason old-style switch loops were compliant with that rule: all the power is coming back via the same wiring path it went to the switch on. In other words, current in on the hot = current out on one of the two travelers, which are both ...


4

Some inspectors will give you a hard time over that usability issue. Three-ways are required in certain hallways and stairways, and an inspector who doesn't know when a three-way is required and when it isn't, might simply reject anything that confuses him. You can purchase a single yoke device with two three-ways, that physically occupies one gang location ...


4

Can't get a receptacle off that circuit Sorry. Kitchen receptacles need to be on 20A circuits, and need to serve only receptacles. Further, the circuit must serve receptacles only in the kitchen, dining and pantry areas. (they can also serve the receptacle that powers a gas range, or a wall clock, but no other loads). Tapping a kitchen receptacle off a ...


3

You can do that if you really, really want to, using common 3-way switches and simply pigtailing the two travelers and neutral at switch 1 or switch 2. I recommend splitting the branches at switch 1, so that when you regain your senses, you can simply get a twin 3-way switch and fall back to the solution A. I. Breveleri recommends.


3

That's a hot, not a ground What you're seeing is an always-hot wire most likely, not a ground, that lands on the terminal screw then continues onward somewhere else in the circuit; some electricians will cut the wire and pigtail, others will use both terminals in a screw-and-clamp, and yet others will wrap a stripped section mid-wire around the screw as you ...


3

It is a 4-way switch. 2 travelers from each direction but no hot or switched hot. You have a 3-way on each b end.You can have any number of 4-ways in between. The reds are carrying switched hot from one end to the fixture at the other end.


3

I feel your pain. In my house I have many panels with multiple switches. In one location I have three 2-ways, two 3-ways, two hot outlets, one switched outlet, and a pilot light. I often stand there and flip sundry switches until I get the result I need. And I'm the person who wired it. There is no widely recognized vocabulary of symbols or colors to ...


3

I find considerable usefulness in neatly printed labels for light switches that are otherwise non-obvious in function. The most puzzling one I actually sorted out (as opposed to various switches to nowhere I've encountered) was a humidistat in a kitchen with no humidifier that turned out to be the control for the stove hood exhaust fan. I labeled that with ...


3

Don't be fooled by Perilex, this isn't 3-phase. Unlike the 'Muricans, who seem to require a dozen or two of different plugs, one for each conceivable purpose, Dutch engineers have come up with the one plug to rule them all, the Perilex. Wisely realizing that there's plenty of situations that call for a mains-voltage grounded plug with more than two working ...


2

ncv's will go off for just about anything. never trust an NCV with your life. cheaper ones will go off from shaking them. i was in a house once where it went off in the entire upstairs. the house was also below large powerlines. knob and tube , switch loops (where there is no neutral or ground) have a larger electric field. also a loose neutral could cause ...


2

What model of switch? Are the lamps incandescent? My answer with the info provided: Pulsating may mean a switch designed for incandescent lamps where ballasts or drivers used with CFL’s or LED’s. These lights don’t have the leakage path that an incandescent lamp has. this would be my guess with the info provided. In some cases older LED’s the switch lamp ...


2

"all 4 wires are yellow" -> an electrician after my own heart! Those are my preferred colors. Here is how 4-ways are wired. As you see, the yellow wires (yours actually are that color) come from 2 different places. A pair of yellows comes from one place, and a pair of yellows comes from another place. Your setup will be in conduit, since ...


2

Based on the diagram (with yellow => white), it looks pretty straightforward, but actual pictures instead of drawings would confirm the details: Box A: Cable 1 = 3-way. Red & Black = travelers. White = switched hot. Cable 2 = Light fixture. Red = switched hot. Black = always hot for use in other stuff past the light fixture. White = neutral. Cable 3 =...


2

The remote shut-off requirement may cause you to choose between two problems: While the remote shut-off is activated the lights can't be turned on locally. Must walk to the remote location and re-enable. or, by using the 3-way as you've drawn, the lights can always be turned on locally -- but you can't tell whether they're on or off from the remote location!...


2

Whomever did this fundamentally misunderstood how three-way switches work. A three-way switch changes which wire (in your case the white/brass screws) is connected to the black screw. One of the two brass screws will always be hot. We call the wires connected to them traveler wires. There's no easy fix with the existing wires here because they tried to make ...


2

This sounds like it would use a double pole single throw switch. Each side of the switch would be electrically separate, but they physically turn on and off together. The relay probably just turns on the pump when any of the switches are on. If this were some sort of 4 way setup, turning the light on in two rooms would turn off the pump. You can test that ...


2

The power and neutral go to all the smart switches. The master must be at the box which has the branch to the light. I am not at all sure that the Leviton supports multiple remotes. But if it does, you'll need to allocate all the /3 wires as follows: Black = always-hot White = neutral Red = Yellow/Red data line


2

You have the wrong replacement switch Your existing switch isn't a 2-way/2-way two-gang assembly like you thought it was, it's actually a 2-way/intermediate (North American translation: 3-way/4-way) two-gang assembly. So, you'll need to get the correct switch before you go any further with this.


2

The light switch wiring itself is straightforward What you have for the two lightswitches is a straightforward 3-way setup with power entering and exiting at the same box. Installing the main smart dimmer in place of switch C and the remote in place of switch A shouldn't be a challenge, since you have separate hot wires for the fan and light running up from ...


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