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Sending data via the power line?No problem with power line communication! EHS and power line communicationThe idea of home automation has been around for many years but it is only recently that the right combination of technical and economic factors has emerged. Over recent years the European Commission (CEC) has sponsored programs of research and development on communications techniques for use in the home. This has led to the development of the European Home Systems (EHS) specification which has defined the rules for a number of communications methods by which equipment will communicate. This specification is managed by the European Home Systems Association (EHSA) and will become an European standard. One of the early barriers to home automation was wiring all the appliances, controllers and sensors together. One communication medium defined by the EHS specification is power line communication. This approach uses one phase of the mainly available power line (230 / 115 V AC) as a communication media. Thanks to this approach it is no longer necessary to install additional cables for communication purposes. All automation equipment is only connected to the power line and is able to communicate on this line. The power line communication uses a so called power line modem to send and receive data via the power line. Our modem was developed using a special chip from ST-Microelectronics S. A., the ST7538P. This modem can be connected to the PC or it can be equipped with an microcontroller card to run an application program. This power line modem with the additional microcontroller card can be installed into many appliances for instance refrigerators, washing machines etc. With this upgrade all these appliances are capable to communicate over the power line. |
