The experimental unit provides a comprehensive experimental introduction to the fundamentals of control engineering using an example of combined flow and level control. The level and flow rate can be controlled individually and as a cascade. In cascade mode the level is the primary controlled variable. The flow control then provides optimum adjustment of the controlled variable to the reference variable (setpoint).

  All components are clearly laid out on a vertical panel. The large-format process scheme provides an aid to understanding. A pump delivers water from a storage tank into a piping system which contains a rotameter. From there the water passes into the transparent level-controlled tank. The level is measured by a pressure sensor installed at the base of the level-controlled tank. The controllers used are two state-of-the-art digital industrial controller. The actuator in the control loop is an electromagnetic proportional valve. Ball valves in the tank outlet and in the pipe system enable defined disturbance variables to be generated. The controlled variable X and the manipulating variable Y can be tapped as analogue signals at lab jacks. This enables external recording equipment, such as a plotter or an oscilloscope, to be connected.

  An instrumentation and control software (RT 650.40) with interface module (USB) is available as an accessory. This enables the key process variables to be represented, and control functions executed.

  The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.

- fundamentals of control engineering
- latest industrial control engineering components:

  controllers, transducers, actuators
- operation and parameter setting of a multi-

  functional state-of-the-art digital controller: e.g.

  parameter setting as P, PI and PID controller
- investigation of disturbance and control response
- influence of different controller parameters on

  stability and control quality
- investigation of the properties of the open and

  closed control loops
- processing of process variables using external

  equipment, e.g. plotter or oscilloscope
- investigating the response of the various controlled

  systems
- control of
  * flow 
  * level
  * level via flow (cascade)
- together with accessory RT 650.40:

  familiarisation with and use of I&C software