The intrinsically-safe Cat® PMC-R control units are used on shearer or plow faces to provide medium to high level of longwall automation. Each Roof Support needs to be equipped with one PMC-R control unit and a solenoid driver to operate the in-shield hydraulic functions and a set of peripheral components, like sensors for pressures and shield advance. The PMC-R can control and display all functions of a shield and is simultaneously the interface between operator and machine (HMI). The PMC-R system can control all individual shield functions based on a reliable network. As an interactive system, it allows the user to execute single shield functions as well as automatic functions. Important process values are continuously displayed as feedback for the operator.