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Would this switch plan work? Answered

I found this online. It would be convenient for switching central lights from two sides of the house when the main panel is on one side.  It's the only diagram I found with the feed coming from the switch, going to multiple lights, and ending at a switch.  I'm having doubts about whether or not it would work and meet US code.  The black taped white wires seem only to be taped at one end, but perhaps I just don't understand.  Any input?



Best Answer 1 year ago

Here is how to wire it Romex or Thin-wall.

Click the pic to see the whole image !


Thanks, Iceng, your diagram is much easier to follow! But I'm still confused... from the power feed switch you've got white, red, black and green. The end switch has black, red, black and green. So what happened to white?

Depends whats on hand. If I only have 2 wire + Ground romex I will need to run two cables. If I have 3 wire + Gnd then there are lots of options.

But here the OP shows (PVC conduit),(Flex conduit) or (Thin-wall conduit) and I can string individual wires like RED & BLK for Hot wire between the switched lines. White wire is for the Neutral and Green for ground. I cart Black, White, Green, Red, Blue and some Bare copper Solid and Stranded in 14, 10 and 12 gauge on rolls plus boxes of romex..

So here I run a Black wire for the Hot which any electrician will recognize at the lamp, also the BLK Hot is the one that gets switched. The WHT lamp wire is recognized by any electrician as the Neutral. And makes adding another lamp an easy future task.

Colors help ID which wire is which.

A] Initially I would pull 2_BLK, a WHT, a RED and a GRN set of wires from left through the lamps to the right.

B] Then pull a BLK clear out of the left side lamp.

C] Then pull a WHT clear out of the right side lamp.

D] Now nut wire the lamps BLK & WHT wires.

E] Wire the Left switch to RED & BLK wires also do 2 GRN Gnd

F] Find the Right BLK wire from the lamps and tie it to the switch wiper.

G] Wire the Right switch to RED & other BLK wires.

H] Wire GRN Gnd to lamps and then to the Right switch.

J] Make sure the breaker is Off and wire the incoming Hot BLK to the Left switch wiper and join the WHT wires.

K] Screw in the lamps and turn the breaker to ON.

L] Try the switches and mark the circuit in the Breaker Box.

Thanks, Iceng! I really appreciate you taking time with this. Over the past couple of weekends I ran 14-3 between the future lamp boxes. Then running on auto pilot from doing umpteen receptical boxes, I pigtailed and nutted the black wires, the white wires, and the grounds. Red I simply nutted and stuffed in the top of the boxes.

I have a diagram with just one lamp between the switches and a white wire marked as black going to the end switch. After counting the wires between the lamps in your diagram, I now understand why using the white wire as black was needed. But I don't know where that change should be made in a series of lamps.

If you have the room in the box for each lamp in a series try to continue with a 14-2 or continue with 14-3 (not using red) from the first lamp to lamp to lamp..

It gets more complicated when you will want to add a third switch which is a 4-way switch,

So when I get to the last lamp in the series going to the end switch, do I mark the white as black and connect it to the switch?

Yes, there are all sorts of products in peel off pages for electricians that have peel off sticky tape strips with numeric different print, to wrap around a wire so you can id a white wire and leave a note for future technical people...

+1 Also your diagram is much easier to read than the pictorial spaghetti-wiring picture attached to this question.

There is more than one way to draw a diagram for something like this.

Some diagrams are full of pictures, like the one you have attached to this question. I mean every object is represented by a small picture, and it looks similar to what it would look like in real life.

Actually the picture you attached kind of looks like cooked spaghetti, but I have to admit, real life electrical boxes kind of look like this too, if you look at them superficially.

Other diagrams are more abstract. The wires are represented by lines. The switches and light bulbs are represented by symbols.

The Wikipedia article for "Circuit diagram" calls these styles "pictorial" and "schematic" respectively.


Interestingly, there's also article for "Wiring diagram"


I think the schematic style (more lines less pictures) is easier to read, easier to see which wire goes where.

Of course, if you want to master this subject, you have to learn how to read both, and how to translate between these styles, and also how to draw your own circuit diagrams.

I claim, the diagram you posted, and the one Iceng posted, are the same circuit. Or they should be the same circuit.

One feature of this circuit is there are two wires that simply "jump", not connecting to anything else along the way, from switch 1 to switch 2.

In Iceng's diagram these wires are colored red and black, and they are drawn as two parallel lines.

In the diagram you attached, one of these wires is red. The other is... wait.... it is hard to tell because there is this grey thing, representing a conduit, or wire jacket, and the color of that second jumping wire changes from black to white-wrapped-with-black-tape, then back to black (and that change occurs inside a conduit!), then back to white-wrapped-with-black-tape.

I think there is something wrong with the diagram you attached, because light fixtures 1 and 2 should be wired in parallel, but they're not. In fact the wiring for {box 1 and light 1} looks identical to the wiring for {box 2 and light 2} as if the author just copy-pasted one to the other.

OK. I guess your diagram is busted. But the one Iceng upped is good, so maybe you should follow his instead.

Plus, it looks like there are two or three 'ibles in the related panel that also describe how to wire "three way" switches.

No it won't work like this as it would violate all rules for elctrical installations.
It does not matter what you try - the Earth wire must not be used for anything but ground/earth, so no chance for a life wire.
You can make the plan work according to regulations if you use three core wire without ground, or for lamps that require a ground connection with 4 core wire.