Lab tests and models

Lab model to visualize the processes in the refrigerant cycle

This model which is equipped with a glass evaporator is used for the basic training courses in order to explain the components and visualize the processes in the refrigerant cycle.

Two manometers and four temperature measuring points help to monitor pressure and temperature changes in the system.

The speeds of the fans at the evaporator and the condenser can be adjusted in order to simulate load changes at the heat exchangers.

The unit is filled with the refrigerant R600a (isobutane).

Fig. 1

Lab model with glass evaporator

Lab model to visualize the processes in the refrigerant cycle

Fig. 2

Laboratory model for controlling the cooling capacity

R744 refrigeration unit for training purposes

The unit shown is used in the R744 training courses in order to demonstrate the function and the operational behavior of such a unit.

The operational data are recorded via a measurement data acquisition system and visualized on the display.

The refrigerating capacity can be measured at different heat loads, pressures, temperatures, air quantities and compressor speeds.

Fig. 3

R744 refrigeration unit for lab tests

Compound refrigeration system with three cooling points

This model is used in the courses “refrigeration technology C” and “electrotechnology with regard to compound refrigeration units“. It consists of three semi-hermetic compressors, three cooling points and an electronic oil control system.

The lab tests deal with the technical installation of the refrigeration unit and test the function of the compound controller and the cold storage controller with thermostatic, pulse width modulated and stepping motor controlled expansion valve.

Fig. 4

Compound refrigeration system with three cooling points and three compressors

Test bench for expansion valves

The refrigerant cycle of this unit is equipped with six different expansion valves connected in parallel.

The function and the control behavior of three different capillary tubes - one automatic, one thermostatic and one pulse width modulated valve – can be tested at changing operating conditions.

The process can be observed in a liquid receiver by means of a glass component.

Fig. 5

Lab model: expansion valves

Lab tests and models

Lab model to visualize the processes in the refrigerant cycle

Lab model to visualize the processes in the refrigerant cycle

R744 refrigeration unit for training purposes

Compound refrigeration system with three cooling points

Test bench for expansion valves

Further information