Carrier current communication for centralised control panels

摘要

The module (128) has communication unit (134) e.g. serial communication bus, such as Modbus(RTM: master-slave type numerical communication protocol), connected between a line start device (104) and a carrier current interface (130) for transmitting information. A carrier current line receiving/converting device (132) transforms transition information in the communication unit from a protocol into representative carrier current signal. The interface has a streamline with an impedance adaptation unit (150) such that the impedance of the interface is able to take different values. Independent claims are also included for the following: (1) a method for examining and adjusting impedance of a command control table (2) an automated method for installation of a table.