Flow and Level control

System

The experiments are set up with experimental panels in the profile frame. The controlled system or control loop is controlled with the Profi-CASSY and the measured values of interest are recorded.

Learning objectives

• Recognising basic control principles
• Management and fault control
• Handling Analysis and Simulation Software

Function

The liquid control system mainly consists of a pump and a storage and measuring tank. The inflow and outflow of the liquid can be manipulated using two valves. The device contains an impeller flow meter with a flow regulator underneath. An immersion tube with pressure sensor detects the fill level in the measuring tank and converts it into an electrical signal for the fill level. The measured variables for flow rate and fill level are shown on 7-segment displays. The digital liquid control system is characterised by its small footprint. It is supplied complete with all sensors and equipment and requires only a few accessories.

Method

The equipment is equally suitable for demonstrations and student experiments. Experimental procedures are carried out using an electronic manual and the measurement files for CASSY Lab 2 and WinFACT. Plug & Play applies: the experiments start automatically after the measurement file is called up.

Target groups

Vocational training in electrical engineering in trade and industry and students specialising in automation technology and mechatronics. The course offers both introductory courses at a basic level as well as challenging topics for bachelor's programmes.

Themes

• Controller design through pole-zero compensation
• Determination of the controller gain Kp from a batch run
• Controller design through numerical optimisation
• Rule of thumb method
• Digital liquid control system
• Flow measurement
• Step response of the flow path
• Flow control
• Flow control at the stability limit
• Follow-up control for flow rate with ZN-optimised controller
• Interference behaviour of the flow control
• Flow control with block-orientated PC simulation
• Properties of the filling level section
• Level measurement
• Integral and PT1 behaviour of the filling level section
• Static identification of the fill level section
• Software-supported controller selection
• Filling level control
• Fault control of the fill level
• Level control with two-point controller
• Level control with PC simulation