One of the three types of Home Automation Systems
Centrally Controlled Communication Systems
Centrally controlled communication systems route signals between a central computer and appliance controllers or environmental sensors. These systems can control some “dumb” appliance as well as “smart appliances. If the controller fails, however, the whole system fails. The major distinction in “smart” home technology is the way electricity is distributed throughout the home.
A control center system allots incoming household electricity to a distribution unit in each room of the house. The distribution unit (or network box) does not provide power to the outlets in the room indiscriminately, as in a conventional home. The new outlets contain microprocessor chips that only provide power upon request by a “smart” appliance. “Smart” appliances have microprocessor chips that enable them to communicate their identity, power demands and functional status to the network box when the appliance is plugged in. If the computer system determines that all is well, the network box sends power to the outlet. If the network senses potential danger, such as a frayed cord, or appliance incompatibility, the system denies power to the outlet. An outlet is only live when utilized by a compatible appliance.
Reference: National Kitchen & Bath Association(NKBA)