Barry:

The JDS Stargate home automation controller supports the Leviton preset dim function as well as the Leviton scene functions. When you define an X-10 device in Stargate, you specify which type of switch it is.

It's true that Leviton uses a different protocol for the preset dim, but unless you are using a home automation controller this doesn't matter. In other words, hand held transmitters (e.g. Pronto) are not capable of sending preset dim commands without the help of a home automation controller to "translate" the Pronto IR commands to preset dim commands.

Regarding noise on the AC power line that may affect X-10 signal communication. I think that both the PCS and the Leviton switch are pretty similar in performance. The PCS switch does allow you to program the minimum X-10 signal strength necessary for it to respond (which is an advantage), but the Leviton switch has "gated AGC" which improves its performance in noisy conditions.

If customers plan to invest money in home automation equipment, they usually expect good performance. That is why I always recommend the installation of an amplified signal bridge (i.e. phase coupler). The amplified coupler bridges 2 or 3 phases of electrical service in your home, and in addition, amplifies all X-10 signals it receives. It actually amplifies a 100mV X-10 signal to 5 to 7 volts on the other electrical phases. This is a 5,000 to 7,000 percent increase in signal strength. Most customers find that when an amplified coupler is installed, it overcomes noise problems and they get very reliable X-10 communication.

Robert
RCI Automation
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