Troubleshooting Electrical Interference

Even though X10 units communicate over wires they can still suffer from interference. The power lines that XI0 uses as its communication medium are anything but quiet. Normally the interference isn't enough to cause problems but some devices in your home can introduce RF interference onto the line, making it hard if not impossible for your X10 devices to function.

A device doesn't have to introduce noise onto the line; it can actually absorb the X10 signal and weaken it. To many devices, the signal from an X10 controller looks like electrical noise and they treat it as such.

Many consumer electronic devices, especially those with microprocessors, have power supplies designed to stop electrical noise from entering the system. These devices absorb and interfere with the XI0 signal if they are close on the same circuit. The following products can cause problems for X10 signals:

- Televisions

- Computers

- Monitors

-Cell phone and battery chargers

- Cable and satellite boxes

- Uninterruptible power supplies

- Surge protector

- Stereo equipment

Monitors, televisions, and other video systems are especially hard on X10 signals because they need very clean power. Electrical noise that enters a TV or monitor interferes with the video signal and appears as static. Because of this, they have power supplies that absorb a lot of power line noise.

It may seem strange that these devices can absorb the signal from an X10 unit, but that is the nature of an electrical current. The power supplies of these devices absorb noise on the line and draw the current. The X10 signal is just electrical current at a specific frequency. In effect, these devices soak up the signal like a sponge.

To prevent signal loss from these devices you can install filters on the outlets that these devices use. These filters prevent the X10 signal from becoming absorbed by any device plugged into a filter.

Determine which device is causing your problem by unplugging any "suspects" and testing the X10 devices. If they work when the device is unplugged but not when it's plugged in, you've found your culprit.