● Demonstrates multi-evaporator system operating at different temperatures
● Incorporates 25 typical system faults, each activated by a push-button switch.
● Allows practical fault detection and location.
● Introduces students to 3 phase systems.
● Two year Warranty.
Introduction
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.
A combination of 25 refrigerant circuit and electrical circuit faults can be activated by the instructor allowing both normal and fault condition operation to be investigated. The faults include:-
Compressor valve fault
Oil separator fault
Overcharge
Undercharge
Check valve leak
Evaporator pressure controller fault
Thermostatic expansion valve not operating – freezer evaporator
Thermostatic expansion valve fault – freezer evaporator
Thermostatic expansion valve not operating – cold room evaporator
Thermostatic expansion valve fault – cold room evaporator
Suction line freezer evaporator – frosted
Suction line cooler evaporator – frosted
Filter dryer restriction
Discharge pressure fault
Hot gas defrosting fault
Suction pressure too low - decreasing evaporator capacity
Suctions pressure too high
One phase fault
Two phase fault
One contact set (motor overload protection) disconnected
Two contact sets (motor overload protection) disconnected
Thermal overload protection of motor switch box
Coil fault – motor protection – starter box
Thermostatic fault – freezing room – not working
Thermostat fault – cooling room – not working
Description
The 811 is one of a range of trainers designed to provide practical training in the fields of Refrigeration and Air Conditioning.
Each trainer has been carefully designed to provide instruction in specific topic areas that trainees are required to study as part of most Refrigeration and Air Conditioning courses.
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.
Further details available on request.
Specification
Detailed
The unit is mounted on a wheeled steel frame with stainless steel base and back panels and incorporates:-
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
Refrigerant: R134a.
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.
Operating Manual
A comprehensive operating manual includes:
Notes on theory and principles
Instructor’s guide notes
Student test papers and sample answers
Electrical wiring diagram.
