DIY Tutorial: How to Wire a Switch to an Electrical Cord

Posted by Snake Head Vintage on Oct 29th 2019

How to Install a Switch onto a Lamp Cord

There are quite a few reasons you might want to add an inline cord switch to your lighting or electrical restoration project: maybe you have no other way to turn the fixture on and off (other than unplugging it!), maybe the switch on the socket is too hard to reach, or perhaps you just want an additional option to make access easier! Here we'll discuss the basics of installing a screw-terminal on/off switch, particularly onto Snake Head Vintage cloth covered wire.

First off, if you've never worked with cloth covered electrical cord before you may want to skim our other blog post "How to Strip and Prep Cloth Covered Cords for Wiring".  Using cloth covered electrical cord is a great way to add a unique flare, pop of color, and authentic vintage feel to any fixture! 

Step by step - Attaching a cord switch:

1) The key to any cord switch is simple: you ONLY cut the HOT wire. All other wires will be left uncut and pass through the channel in the switch. Functionally, the switch acts as a circuit interrupter: in the "off" position, the switch is not completing the connection through the hot wires, in the "on" position, the switch is allowing the circuit to be completed.

Inline cord switch internal wiring diagramThe hot wire will be BLACK, or "unmarked", whereas the neutral wire will be WHITE, or "marked", as in with a tracer stitch on the cloth, or a stripe on the wire under the cloth. So: hot gets cut, neutral does not. If there is a green ground wire (like on our 3-wire round cords), the green wire also remains uncut.

Exceptions: sometimes the wire coloring will be different, brown is sometimes used as hot instead of black, and blue is sometimes used as neutral instead of white. With 2-wire parallel cord, the marking is on the side of the wire: the smooth side is hot, the ridged side is neutral.

2) Decide where you want your switch to go! Things to consider: where will this fixture be going? Where will the nearest outlet be, and do I want the switch closer to the outlet, or closer to the fixture? If you are wiring a lamp that needs a lot of cord internally, be sure to account for that: a common place to put a switch is 1 to 2 feet from the base of a lamp. Others will choose to place it a few feet from the plug in order to have the switch closer to the wall, or sometimes halfway down the line, if that allows you enough slack to raise the switch access up onto a desk or nightstand level.

Where to install your inline cord switch

3) For twisted cords, cut the hot wire in the center of where you want your switch to be located. If you can't tell which wire is hot from the outside of the cloth, you have a few ways to figure it out: you can trace the line from one end of the cord, or you can carefully peel back the cloth in a little spot on one of the wires. If you guess right, great, cut it! If you guess wrong, well that spot will be covered within the switch anyway, no biggie. Cut the hot wire and strip both ends, you can use a thin piece of electrical tape to better hold the cloth in place and prevent it from fraying. Route the uncut neutral wire through the pass-through channel. Wrap the stripped ends of the hot wires around the screws under the head, wrapping in the same direction that the screw will be turning: you want to pull the wire in further as you tighten it, not push it out.

Inside a lamp on/off switch

4) For round cords and overbraid cords, you will first need to cut through any outer cloth or vinyl jacket that is covering the internal wires. Tape off the spot where you need to cut, and use a razor knife to VERY CAREFULLY score the outer cloth (and if it's a 3-wire round cord, the outer vinyl jacket directly under the cloth) and remove it, exposing the wires inside. Cut the hot wire in the center and proceed to follow the same procedure provided in step 3 to make your connections

how to install a lamp toggle switch wiring diagram of a lamp cord switch

  • Pro Tip: We recommend these switches for the round and overbraid cords, they have a larger opening that makes it easier to fit the wiring into. If you choose to use one of our other switches on a round cord, you can also opt to file out the opening a little: the plastic is easy to file and it doesn't take much to open it for a easy accommodation.

5) For parallel (flat) cord, the process is similar as the other styles of cord except that you will also have to split the two wires apart from each other. After taping off where you intend to place the switch, use a razor knife to first remove the cloth from the cord, then cut into the center of the 2-wire molded wire and carefully separate the two wires from each other. You will now have a hot and neutral wire (remember, hot is the smooth side, neutral is the ridged side). Cut the hot wire and proceed to connect your wires the same way we described in the last two steps.

2 wire parallel cord with a cord switch installed

6) Once everything's connected, place the cover back on the switch and fasten the screws back in place. Flip that rocker on and off a couple times, behold your incredible power to control the flow of electricity with a single finger!

How to install a switch onto a lamp cord

That's it! Now let's get creative!