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BUILD A VIRTUAL WIRELESS AUTOMATION SYSTEM

by Michael Chan

Start ý X-10 ý The Scheme ý The Interface ý The Construction ý Sources and PDF

X-10

X-10 signals are device-controlling codes superimposed on the AC lines. These signals ride on the AC power waveform as the carrier and travel down the AC lines to reach the controlled devices. The X-10 Home Control System was first introduced in 1978. Since then, X10 has developed and manufactured convenient home automation modules with the patented X-10 standard. All these modules are essentially transceiver appliance controllers, which are capable of transmitting and receiving X-10 signals via the in-house AC power lines.

An attractive feature of X-10 modules is that all of these units are plug-ins to the common AC outlets and, therefore, require practically no extra installation and wiring work. There are two dials on each module that are set to give it a unique identity within a controlled system. The two settings, which represent the house codes and device codes (see Table 2), offer a total of 16 ý 16 possible controlled devices for a given system. Some of the handy X-10 modules can be seen in Table 3.

SAFETY COMES FIRST

This project makes use of phone and AC lines as the media of communication. Before you start to work on the project, be aware that you are working near high voltages. The ringing signals across the phone lines could be as high as 130 VAC, and the DC operating voltage is between 45 and 105 V. Nominal voltage across the AC lines in North America is 110ý125 V_RMS, and peaks at almost 180 V relative to ground. Transients caused by induction, lightning, or electrical faults can create even hazardous overvoltages. Therefore, exercise extreme caution when you work on the project.

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