Thermodynamic Cycles of Reciprocating Machines


Compressed air for industry and businesses that use compressed air as an energy source is generated by means of so-called compressed air generation systems. A key component of these systems is the compressor. It converts the supplied mechanical energy into a higher air pressure. Such systems are used to drive machines in mining, for pneumatic control systems in assembly plants or tire inflation systems at petrol stations.

TFM- 500 includes a complete compressed air generation system with a two-stage compressor and an additional pressure vessel as intercooler. The trainer enables the recording of compressor characteristics and representing the compression process in a p-V diagram. The air is sucked into the intake vessel through a measuring nozzle and calmed there before it is compressed in two stages. The additional pressure vessel for inter cooling is located between the first and second stage. After the second stage, the compressed air is pressed into another pressure vessel through a cooling tube. To achieve a steady state, the compressed air can be released through a blow-off valve with silencer.

Safety valves and a pressure switch complete the system. Sensors measure the pressures and temperatures in both stages as well as the electric power consumption. A nozzle at the intake vessel serves to determine the intake volumetric flow rate. The experimental unit is operated via a touch screen with intuitive user interface. By means of an integrated router, the experimental unit can additionally be operated and controlled via one end device and the user interface can be displayed on up to 10 end devices (screen mirroring). Via the PLC, the measured values can be stored internally.


  1. Recording the characteristic of a two-stage compressor
  2. Piston compressor with 2 cylinders in V-arrangement
  3. Plant control with PLC, operation via touch screen
  4. Integrated router for operation and control via an end device and for screen mirroring: possible to mirror the user interface on up to 10 end devices
  5. Intake vessel with nozzle to measure the intake volumetric flow rate, pressure sensor and additional manometer
  6. Pressure vessel after the first stage as intercooler
  7. Pressure vessel after the second stage with safety valve, blow-off valve and silencer as well as an additional manometer and a pressure switch
  8. Sensors for pressures, temperatures and electric power output data acquisition via PLC on internal USB memory.

Technical data

  1. PLC
  2. Compressor
  3. two-stage
  4. with 2 cylinders in a V-arrangement
  5. power consumption: 3kW
  6. speed: 710min-1
  7. intake capacity: 250L/min
  8. quantity delivered: 202L/min (at 12bar)
  9. operating pressure: 12bar, max. 35bar
  10. Intake vessel: 20L
  11. Pressure vessels, 16bar; capacity:
  12. after 1st stage: 5L
  13. after 2nd stage: 20L
  14. Safety valve: 16bar
  15. Measuring ranges
    1. differential pressure: 0…25mbar
    2. pressure: 1x 0…1,5bar; 2x 0…16bar
    3. temperature: 4x 0…200°C
    4. power: 0…3500W
  • 400V, 50Hz, 3 phases; 400V, 60Hz, 3 phases
  • 230V, 60Hz, 3 phases; UL/CSA optional
  • Dimensions and weight
  • LxWxH: 1770x800x1520mm
  • Weight: approx. 304kg