Control Lights in Your House With Your Computer




Have you ever wanted to control the lights in your house from your computer? It's actually fairly affordable to do so. You can even control sprinkler systems, automatic window blinds, motorized projection screens, etc. You need two pieces of hardware to get started. A controller, which connects to your computer; and a dimmer switch. I'm using SmartHome Insteon products in this example.

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Step 1: Install the Switch

Follow the instructions provided on how to install the switch. The switch I'm using is Insteon brand, but there are other types of remote controllable switches such as X10. These switches require the neutral line to send signals (commands) over. If your switch box doesn't have a neutral, you're in trouble. Try contacting an electrician to see what you can do.

Step 2: Install/setup Controller

You need a controller which will send commands over the power lines to your switch. I'm using the Insteon PowerLinc Controller with a Serial connection. This works with Windows and Mac. Windows has freeware easily found on Google.

Setup was easy. I plugged it into the wall outlet, plugged the serial connector to my PC, and that's it.

You need to download and install SDM SmartHome Device Manager. Now, once you've installed this, you can start sending commands to the PLC (PowerLinc Controller).

Since I had a MacBook in another room, I installed SDM Socket Server, which is freeware for Windows. This let me connect over TCP/IP from upstairs and send messages downstairs. Note: you need to edit a registry setting to make this software work with the Serial (COM1) port. HKEY_USERS\.DEFAULT\Software\Smarthome\SmarthomeDeviceManager
The port needed to be changed from USB4 to COM1.

Here are some various programs you might also find useful.

Step 3: Play Around With a Script

I made a Python script that basically just connects to the SDM socket server and sends messages to the PLC Controller downstairs. You can do fun stuff like flashing the lights on and off. A more practical thing to do is setting it on a timer to wake you up in the morning. Actually, you can program timers into the PowerLinc Controller directly if you use InHomeFre or other software.

You have a little more control when you code the script yourself.



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    49 Discussions


    Reply 4 years ago on Introduction

    I am not sure but you can try the lighting control solution here

    HAHAHA! get a PLC for free? Braski if it was possible to get one of those mothers for free my entire house would be marquee lighting lol.


    9 years ago on Step 2

    out of curiosity, how did you install the socket server on mac? in a VM or? oh and, is there any chance you wil release the code for your python script?:) Great project btw.


    9 years ago on Introduction

     So let's say my dad and I decide to do this, could we both control the same system from both of our computers? Possibly at the same time?

    1 reply

    Reply 9 years ago on Introduction

     You can control from multiple locations/controllers. As long as the commands are sent approximately one second apart it should work as far as I know. The switch devices are just sitting on the line waiting for commands. They don't care where the commands come from. I haven't messed with this in a while so I am not sure if they have made any improvements recently.


    Reply 9 years ago on Introduction

     I think it will run around $90 to $200 depending on how many switches you want.

    if you go with the infared controll idea its possible to redo your house to work of a Wii remmote....hmm...sounds like a good idea. im guessiig that the main problem would be to make the remote stilll compatable with the Wii. it be weird if your playing and suddendly the power cuts off

    1 reply

    A better idea might be to use the bluetooth connection of a Wiimote with a pc, that way you avoid issues with line of sight the comes with using infrared.  The only problem I see with this is that if you wanted to switch back and forth between using the Wiimote with your pc and the Wii you would have to manually sync it each time with either system.