Electrical – Rewire a string of lights using 14/3 or can I add a red wire

electricalmultiway-switchwiring

I have a situation where I have a switch at the bottom of the stairs that turns on a set of canned lights on the same circuit. The current wire used is 14/2.
I am in the process of finishing the basement and my wife wants me to add a switch at the far end of the hall to shut off or turn off the same lights on the string.
My question is will I have to purchase 14/3 wire and rewire everything or can I just add the traveler separately.
I didn't by the 3 way switches yet so if there is a tip on how I should tackle this please let me know.

I have attached an image in what I believed was the correct approach. However, the power source is going to the fixture first whereas the power source is going to the switch first.
Can I achieve what this picture is showing by adding a 14/3 wire from the one switch to the other? In the picture it shows one light but I have 6.

14/3 Wire Example

Best Answer

With traditional switches

You are using the word "traveler" in singular. 3-way switches do not work that way. They need 2 "travelers".

So if you are currently supplying hot and neutral down that /2 cable, you cannot simply add "a traveler" to the pair. You need to add 2 travelers, so you need /4 cable, which is expensive, or in some cases, /5 cable, which is unobtanium.

So you are actually better off leaving the /2 cable in place doing whatever it's doing... and adding a /3 cable between the two switch locations. This will keep the wiring simple.

With smart switches

Smart switches either need 1 traveler, or 0 travelers, depending on their particular design. With the right smart switch, you may not need to do any modifications to the wiring. Shop carefully and save yourself some trouble!

Related Solutions

Electrical – How to wire two lights with a switch

Here's a quick ascii art diagram of what you need to have:

Power source       First Light   Second Light   Switch
   |  |               |   |         |   |        |  |
   |  |               |   |         |   |        |  |
   |  + white/neutral ----+---------+   |        |  |
   |                  |                 |        |  |
   |                  +-- red/switched -+--------+  |
   |                                                |
   +------- black/hot-------------------------------+

Between the second light and the switch, you can run a 2 wire line (just replace the red line with the white and tape the ends of the white with black tape to indicate it's a switched hot). However, between the first and second light, you'll need a 3 wire line to handle the hot/neutral/switched combination.

enter image description here

Wiring – Wire in two lights to a switch plus a fan to a switch when power is coming in between the lights without using 14-3 wire

They make products specifically for that problem. You wire hot, neutral and ground to every location (i.e. 14/2 wire) and the switch, lamp controller and fan controller uses digital signaling to send the on/off command over the 14/2 or wirelessly. Some can also be controlled by your smartphone etc.