Longwall support control for controlling the movements of longwall support units in the longwall of a mine

A longwall support control for controlling the movements of a plurality of longwall support units in the longwall of a mine, comprising:

• a central control system;
• and
• a separate mining shield control device locally and operationally associated to each longwall support unit, the mining shield control devices connecting to the central control system and serially connected to one another by means of at least one bus line, through which control commands can be fed to all of the mining shield control devices from the central control system or an adjacent mining shield control device, each mining shield control device storing a code word uniquely associated with the respective mining shield control device, wherein signals that are fed via the bus line do include a code word, and with each mining shield control device being programmed such that those signals received via the bus which include that code word associated with the respective mining shield control device are delivered for execution to that mining shield control device,
• wherein the mining shield control devices connect via a parallel second bus line to the central control system and to one another, and all digital signals including control commands and measuring signals can be fed by the first or the second bus line, and
• wherein each of the mining shield control devices is programmed such that signals that are received via one of the bus lines, are delivered to an input element for executing at least one of the following measures:
• delivering signals which do include the code word associated with the respectively called up mining shield control device to the respective operational element of that mining shield for execution;
• releasing at the same time and without substantial delay an acknowledgement signal on the respective other bus line acknowledging receipt or execution of the command signal;
• or feeding signals that are received via one of the bus lines, and which do not include the code word associated with the respective mining shield control device to an amplification element for amplification and transmittal to the adjacent mining shield control device.