Level Process Control Trainer
(CT-021)

1.Tanks, 2.Pump, 3.Pressure sensor, 4.Propotional valve, 5.Schematic diagram, 6.ON/OFF trainer switch, 7.Emeregncy button, 8.Valve indication LED, 9.Pump indication LED.

  • Familiarization with types and functions of different control systems
  • Investigation of open loop circuit
  • Investigation of closed loop circuit
  • Demonstration of different types of PID controllers used to control liquid level:
    • P-controller
    • PI- controller
    • PID- controller
  • Tanks
    • Volume
      • Lower tank volume: 6 liters
      • Upper tank volume: 2.5 liters
    •   Material: acrylic
  • Pump
    • Voltage: 12-volt, DC
    • Flowrate: 10 L/min
    • Pressure: 0.5 bar
  • Proportional valve
    • Flowrate: 1.1 m3/h
    • Port size: ½ inch
  • pressure sensor
    • Pressure range: 0-100 mbar
    • Output signal: 4-20 mA
  • Level process control trainer - (CT - 021)
  • BEDO Software + USB cable
  • Hard copy user manual
  • Laboratory PC

Level process control trainer is a benchtop unit that features one of the most important industrial applications of PID (proportional – integral – derivative) controllers which is the level control. The trainer allows trainees to regulate and control the liquid level using PID controller. The trainer aims at demonstrating the principles and function of PID controller, effect of manipulating the controller variables on the control system, as well as the limitations of each control system (P,PI & PID).

                                     
  • The educational unit features an industrial process of level control using PID controller to study and investigate its operation.
  • The trainer provides wide range of experiments to study the effects of different controller parameters (P, PI, PID) and their influence on the closed loop system response.
  • Printed on the unit front panel a schematic diagram of the system process features the main control elements such as : the controlled variable, disturbance source, measuring element and its feedback, PID controller and the final control element (actuator).
  • The system process consists of two tanks, a pump, two level measuring elements and a proportional valve.
  • Both tanks are made of transparent material to provide a better observation of the process.
  • The pump is mainly used to deliver water from the lower tank to the upper tank.
  • The pump also works as an actuator which responds to the signals received from the PID controller to eliminate the system errors as well as maintain the system stability.
  • The included proportional valve is used to introduce disturbances to the system by varying the size of flow passage.
  • A pressure sensor is included to measure liquid level in the tank by using the hydrostatic pressure equation P=ρgh.
  • The measured pressure head (h), also known as liquid level, is converted into a signal that can be transmitted to the PID as a feedback.
  • A measuring scale is printed on the upper tank to ensure the readings of the sensor are accurate.
  • The system is supplied with a S/W to monitor, record and control the process, as well as to alter process settings when experimenting with different control systems.
  • Software allows trainees to visualize the main differences of the system response curve due to the change of control gains P, I and D and to study the effect of each gain on the system response.
  • Process parameters can be instantly displayed on a PC (not included) using USB socket and data acquisition software.
  • The unit is supplied with two LEDs indicating the operation state of the pump and the valve, in addition to the ON/OFF switch and emergency button.
  • The unit is equipped with two handles for easier mobility.