The Advanced Training Unit for Fault Location 811 is a fully operational refrigeration unit with two visible evaporators simulating freezing and cooling rooms, operating from a single semi-hermetic condensing unit.
The unit is constructed entirely from standard commercial components, including all of the necessary primary and safety controls and will give students valuable experience of system adjustment and fault finding on a multi-evaporator three phase refrigeration system.
On the model 811 all standard components are visible, mounted on a steel frame with stainless steel panels. Instrumentation includes condensing, evaporating and suction pressures, mechanical and digital temperature measurement, digital multi-meter and optional refrigerant flow meters. The system includes reverse gas defrost, suction accumulator, oil separation and variable speed evaporator and condenser fans.
Instructor controlled faults are induced by internal components which are hidden from student view. A standard Student Tool Kit, and Test and Service Equipment Package are available as optional items.
Compressor: Semi-Hermetic, 0.37 kW. 1450 rpm
Condenser: Air-cooled, aluminium finned, copper coil
Evaporators: Display-case evaporators. Aluminium finned, copper coils with hot gas defrosting
Injection controls: 2 thermostatic expansion valves
Liquid receiver
Control equipment:
– Low and high-pressure control
– Thermostatic control
– Evaporator pressure control
– Capacity control
– Condensing pressure control and crankcase pressure control
– Low pressure switch
– High pressure switch
Measuring equipment: Digital temperature indicator with 10 ways elector switch
4 pressure gauges (3 compound,1 high pressure)
2 dial thermometers.
Hand-held digital multi-meter
25 switches located on the side panel under a hinged cover allow combinations of faults to be activated by the instructor.
An electrical control box is mounted on the panel and includes accessible three phase relays, fuses and an overload protector. An internal three phase residual current device protects against earth leakage. Fan speed controls and defrost switch with indicator are also panel mounted.