AZM6151 Capacity Control and Faults in Refrigeration System Educational Equipment
Technical Description
The efficient control of the capacity and temperature in refrigeration systems is an important topic in refrigeration technology. With different methods of capacity control can be investigated.
The components of a refrigeration circuit with refrigeration and freezing chambers are arranged clearly in the trainer. Solenoid valves enable the separate or parallel operation of the evaporators in the two chambers.
The circuit is equipped with a capacity controller, a start-up controller and
a combined pressures switch for the delivery and intake sides of the
compressor. One heat exchanger each in the inlet of the two evaporators
enables the supercooling of the refrigerant to be investigated for the
efficiency of the process. The refrigeration capacity of the two individual
chambers is controlled by a thermostat. The refrigeration chamber also
features an evaporation pressure controller.
There are two defrosting methods for the freezing chamber: an electric
defrost heater and a hot gas defrosting where hot refrigerant is fed directly from the compressor in the opposite direction through the evaporator.
The simulation of 12 different faults, such as e.g. faulty valves or clogged pipes, is activated using a touch panel PC.
Relevant measured values are transmitted directly to the touch panel PC and analysed. The software enables e.g. the representation of the cycle in the log p-h diagram.
The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments.
Learning Objectives / Experiments
– familiarisation with the key devices for changing the refrigeration capacity
* thermostat
* capacity controller
* start-up controller
* evaporation pressure controller
* condensation pressure controller
– fault finding in refrigeration system components
– effect of refrigerant supercooling
– familiarisation with defrosting methods
* electric defrost heater
* hot gas defrosting
– representation of the thermodynamic cycle in the log p-h diagram
