The Essentials ofProcess Control (EPC) range of products takes students through the fundamentalsand principles of process control and progresses to give them a thoroughgrounding in the control of physical processes. Four independent process unitsdemonstrate level, flow, temperature and pressure as the controlled variable.The concepts of closedloop control, including on/off control, proportional control, proportional/integraland proportional/integral/derivative (PID) control can be explored anddemonstrated. Some units also cover both time proportioning and analoguecontrol of the same parameter. Each process is supplied complete with softwarethat allows it to be controlled using a Windows PC via a USB connection. Theeffect of making changes to the system or to the controller configuration canbe quickly investigated by applying repeatable disturbances or step changes tothe process. Comparison of the responses obtained with different controlsettings clearly demonstrates the need for correct matching of the controllerto the system characteristics.To demonstrate industrial control systems, two further controllingdevices are available, a full function commercial PID controller with autotune,and a programmable logic controller (PLC). The plc has the control algorithmsimplemented in ladder logic and so are fully accessible to the user. Anotherfundamental aspect of process control is an understanding of sensors and howthey are calibrated. This is demonstrated by a sensor calibration apparatusdesigned specifically to demonstrate this subject.