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Home Automation with Mac OS X, Part 2

by Alan Graham

The first article in this series focused on the basic equipment you'll need to set up a home automation system. In this installment, I'm going to dig deeper into the hardware and show you some tips I've learned from my experiences.

Before I do that, however, I want to address some of the questions that arose form the first article. So let's start with a quick Q&A.

Home Automation Q&A

Q: What about cost? Could you give us an idea of how much it cost for all your home automation?

A: I have quite a large system. However, let's just look at the backbone of my system as it pertains to this article:

  • 2 transceiver modules
  • 1 PowerLinc USB
  • 1 copy of Indigo home automation software
  • 3 Appliance modules
  • 1 Super socket module
  • 2 lamp modules
  • 3 wall switch modules
  • 3 2-way lamp modules
  • 2 socket rocket lamp modules
  • 2 screw-in lamp modules
  • 1 keychain remote
  • 1 super remote
  • 1 palm pad controller
  • 2 slimline switches
  • 3 motion detectors
  • 1 SignalLinc plug-in phase coupler

Using a combination of eBay and the X10, Smarthome, and Perceptive Automation sites, I found that I could buy all of these items for about $430. Your mileage may vary (your needs may also be less/more than mine). I would also like to point out that Smarthome manufactures a number of X10-compatible devices that are not only affordable, but also more versatile than their X10 counterparts. I'm focusing more on X10-branded components, because that is what I have.

Q: I have had a terrible time with X10 gear. The controllers and wall switches frequently stop working; lights turning themselves on and off and so on.

A: More often than not, this is caused by line noise or appliance interference. If you find this problem exists, try using a noise filter, like the Smarthome FilterLinc.

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Other reliability issues can be caused in larger homes. When X10 signals travel through the house, they tend to go everywhere, and not directly to the intended receiver. Along the way, the signal becomes weakened. Try using a Smarthome BoosterLinc to fix this.

Q: I would love to set up my home with this stuff, but I do not care to dedicate a computer to the monitoring of it. Is there such a critter as an intelligent interface that can handle timed events and such?

A: There are a number of solutions for this. X10 has an affordable device (the CM-11) that can "store" schedules and macros, and run them without a dedicated computer. However, this device is serial, not USB, and thus requires a serial adapter (an additional expense). It also has very limited controls (no conditional logic). Indigo can control the CM-11, but cannot upload macros and schedules to it.

Q: I'm curious to learn if you can set up a simple security and monitoring system for the home that can let me know whether somebody has tried to enter our house while we're away on vacation or at the office?

A: There are a number of ways you can do this. I'll cover it in a future article.

Q: I've heard a lot about home automation, but it always seems to be for a 110V environment. I am wondering what tools to use in a 240V environment. Can I use the gadgets you suggest in my 240V home? If not, what substitutes are available?

A: While the devices and the home I am describing are 120V, you can find X10 240V alternatives. The names might be different, but the functionality is the same. Try looking here:

Q: I really like the idea of some home automation, but I would also like to add some data collection and reporting. For example: fuel level in an oil tank (or propane), fuel consumption rates, temperature levels in various rooms or areas in the house, measuring electricity usage at various circuits, etc.

A: I'll cover a lot of this in future articles, including the use of a database to track and control your home, based on calculations. In the future, we'll also build a touch-screen kiosk version of our home automation solution.

Q: Do I need home automation software for a basic solution?

A: No. X10 modules can work independently of a computerized solution; however, your level of control is severely hampered. While you can dim and control the on/off effects of appliances and lighting, there is no conditional logic. So, for example, you could not designate a setting such as:

If sunrise = yes, turn on devices A1, A2, and A3. Dim A3 to 50%

Configuring a Home Automation System

Now it's time to start designing a solution from the ground up. In this article, I'm going to focus on hardware. In the next installment, I'll cover the software aspects. But before doing any of this, I want to take a moment to discuss how X10 technology and home automation works.


The X10 technology is surprisingly elegant and simple in its design and execution. Every module has a house code (A-P) and an individual unit code (1-16). By assigning each module a specific house code and unit code, you are able to designate which module will respond to which signal. These signals travel over your home's existing wiring, so you don't need to retrofit your house.

Let's look at some examples of how this works.

Example 1: Basic Transceiver Setup

In this example, the wireless remote sends out a signal that tells module A2 to turn on. The RF signal is picked up by the transceiver, which in turn sends the signal A2 On across the electrical wiring in your home. When module A2 hears the command, it turns the lamp on.

Example 2: Basic Indigo/PowerLinc Setup

The Indigo software is set up to automatically turn device A2 on when the sun goes down. At sunset, it send the signal A2 On to the PowerLinc USB device, which then sends the same signal through your wiring to the lamp on A2.

Example 3: RF/Indigo/PowerLinc Setup

The wireless remote sends the RF signal A2. The transceiver takes the signal, converts it, and sends it through the wiring. The PowerLinc device hears the A2 signal and passes that info on to Indigo. Indigo knows when it receives the A2 command to turn on lamp A6. Indigo tells the PowerLinc device to send out A6 On.

It is important to note that transceivers, regardless of their house code setting, are always unit 1 To increase their usefulness (and thus not lose a number), you can plug a small appliance or non-dimmable light into the transceiver.

Designing A Solution

In deciding how your system should work, it is smart to plan ahead and think of the areas you wish to control. I like to think of them as zones. It helps to sketch these out on paper before you purchase your X10 equipment.

Four-one Solution

In the above illustration, we have the first floor of a house, divided into a number of different zones. Each zone has a different house code. You wouldn't necessarily configure your home this way (it's not efficient), but this makes for a good example of all of the possibilities.

Entryway: House Code A

In the entryway, we have one light, so one unit code. Very simple.

Living Room: House Code B

The living room has four lights, all with different unit codes. This allows you to control each light individually. You can also control all of the lights as a group, using home automation software. This gives you a wide variety of lighting configurations and effects.

Dining Room: House Code C

All of the lights in the dining room must be controlled as a group, since they all listen for the same house/unit code. You might use this for a combination of chandelier and track lighting. The problem is that you cannot control any of the lights individually, which could be a problem if one of the fixtures cannot be dimmed.

Kitchen: House Code D

This combination might be used for an overhead light fixture, in combination with track lighting or under-the-cabinet lights. For example, you might have a setting that turns on all of the lights to 100% for "cooking," while a "night light" setting automatically turns off the overhead lighting and dims the cabinet lights later in the evening.

Again you don't necessarily want to have each room on a separate house code. For one thing, each house code requires a separate transceiver (for RF control), so your cost goes up. Secondly, this adds a level of complexity when it comes to using remotes. Lastly, you can control up to 16 devices for each house code. That's a lot of items.

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