Abstract: An electrical power control system is adapted for controlling power and lighting in a building. Switch controls have either relays or triacs, controlled by microprocessors, to switch power on electrical branch circuits. An interface device 122 communicates with the switches 124,126, arranged in a multidrop configuration, with variable length data packets over serial branch circuits or data buses 142. In addition to being controlled by the interface device 122, the switch controls also have local switch actuators. The actuation of the local switch controls can be used by the interface device 122 as a control inputs to initiate other actions. Adaptive polling of switch controls is used to minimize system response time, and both transmit and receive signals are carried between the switch controls and the interface device 122 at different times on the same twisted pair wires. The interface device 122 can also communicate with a home automation system controller.

Abstract: A dimmer for use in lighting control in which a triac control circuit in included which allows for control of both incandescent and low voltage lighting systems at low and high intensities 142,144. The triac control circuit includes a microcontroller 130 which alters the duration of the gate triggering pulse for the triac 134 based upon the desired intensity level of the load. This dimmer is used in a lighting control system and the dimmer is responsive to a system controller 2 as well as to momentary switch inputs which are made directly to the dimmer. The triac control circuit can also be used with other inductive loads.