Build an X-10 Lamp
by Doug Smith
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One of the most difficult things about home automation is making the technology work in an intuitive way. A good example is connecting a lamp using X-10 technology. It's simple to plug in a lamp module but awkward in every day use. You can turn the lamp on with the normal switch but not off again. You must use another controller. I know that many people leave an X-10 mini controller next to each lamp for this reason. And even worse, if you accidentally turn the lamp switch off, then it can't be operated remotely.

My solution has been to build X-10 modules into my lamps. They can be turned off, on, and dimmed, both locally and remotely with no restrictions. It's completely intuitive and the switch is often in a much more convenient location than in the original lamp.

You can build your own X-10 lamp for under $20, not including the lamp.

Please remember that we're dealing with line voltage which can give an electric shock if not handled properly. If you're not comfortable working with that or don't have at least a little soldering experience, then get some help or don't attempt the project. Now with that out of the way, lets get on with the project.

X-10 lamp modification parts

Here is what you'll need:

  • An X-10 WS4777 3-Way Wall Switch Module.
  • A lamp with enough room in the base to mount the WS4777.
  • Extra wire the same guage as that used in the lamp.
  • A momentary push button switch rated for line voltage. I found the best switch in the electrical section of my local hardware store.
  • Wire nuts.
  • Solder, hot glue, and some basic tools.

Preparing the lamp: Start by making sure the lamp is unplugged. Decide where the WS4777 will be mounted. Cut out an opening if needed. All of my lamps have the module located in the base, facing down so the house and unit code wheels are accessible.

Find a good location for the push button switch, drill a hole for it, and mount it. If the lamp already has a dimmer built in, it will need to be removed so it doesn't conflict with the dimming feature of the X-10 module. This could be a good place to mount the new button.

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cutting X-10 wall switch plastic

Modifying the WS4777: Disassemble the module and remove the circuit board. The front plastic case contains a slide switch which pops out easily and a plunger switch which can be partially removed. The part of the case that surrounded the plunger will probably need to be removed for the module to fit in the lamp. I like to use a cutting wheel on my dremel tool to take it off quickly.

X-10 wall switch circuit board modifications

The plunger switch will no longer be used so those parts and contacts can be thrown away. The slide switch is normally used to cut all power to the light when you change the bulb. But they always seem to get slid over to the off position and my lights don't work as expected. Most of us change a light bulb occasionally with the power on anyway, so I disable the feature. Besides, we just removed the plastic part to get it out of the way. Soldering a jumper between the contacts will fix it and save you from having to reinstall the little metal contact that activates it. I usually just cut a chunk of the metal contact and solder that in place.

While you have everything apart, you might as well enable local dimming by soldering a small jumper across the set of contacts shown in the picture. With this enabled, you can press and hold the button to cycle through the dim levels. A normal momentary press of the button will still turn the light full on or full off.

Put the house and unit code wheels back into position and reassemble the switch. Fill the opening in the front with hot glue to make sure nothing gets in there and shorts out the circuit board.

Wiring diagram Putting it all together: Wire everything up as shown in the diagram. Use wire nuts on all of the connections and be sure there are no exposed wires. Make any last changes to the module so it will fit. On one lamp I had to trim part of the metal mounting fins. Try not to take too much of the fins off since they also act as a heat sink. Mount the module and any dangling parts in the lamp with hot glue.

Many lamps have a switch up near the light bulb. I like to also make sure that switch is turned on then cut off the shaft to prevent it from being used accidentally. It's no longer needed with the new switch anyway.

Test it out. If everything works properly then perhaps it's time to sit under your new lamp and enjoy a good home automation book.

WS-467 Modification

Project Update: I had actually built my first lamp using a regular X-10 WS467 wall switch module instead of the three-way version. Since I received some e-mail asking if it could be done this way, I decided to detail it here.

The circuit boards for the three-way and the regular wall switch module are exactly the same. The three-way version has a few additional parts connecting an extra wire for the remote switch. The extra parts seem to be used to reduce noise over a long wire run through walls. Since this is being built into a lamp with relatively short wires, we can skip those parts and just solder in the needed wire. Here's a picture of how it's done.

It's a little more work, but not too bad considering the project requires some soldering anyway. And it saves a few dollars by not only using a cheaper switch, but one that you're more likely to have in the "junk box" with a broken button from use in the house.