Vaccine storage capacity: 92 L
Volume category: >/= 60, <120L
Solar radiation reference period of 3.5 kWh/m²/day and hot zone (+43°C) test temperatures.
Operating temperature: Min and Max rated ambient temperature: +5 °C and +43°C
UIFPF: Grade A
PQS prequalified Solar direct drive refrigerator with no battery for storage of vaccines at +2 ?C to+8?C in areas without any electricity, or where there is less than eight hours of reliable electricity over a typical day.
Refrigerant: R600a, 50 grams.
The Absorption Refrigeration Cycle Study Unit is an extremely easy-to use and functional unit able to permit the study of an absorption refrigerating cycle. The cycle peculiarityis to generate low temperature using an heat source. The heat can be produced or by an electric source or by a gas burner.The cooling fluid is ammonia (NH3), housed in a sealed circuit. Afront panel with mimic diagram and instrumentation allows to keep the most significant thermodynamic quantities undercontrol, so facilitating the students understanding and the teachers task. The unit is supplied with the electric resistance heater, but it is possible, on demand, to have the gas burner. A refrigerating room allow the cooling effect visualization. The main characteristic of the Absorption Refrigeration Cycle Study Unit is to enable the student to observe the absorption refrigerating cycle.
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Vaccine storage capacity: 170 L
Volume category: >/= 60, <120L
Solar radiation reference period of 3.5 kWh/m²/day and hot zone (+43°C) test temperatures.
PQS prequalified Solar direct drive refrigerator with no battery for storage of vaccines at +2 ?C to+8?C in areas without any electricity, or where there is less than eight hours of reliable electricity over a typical day.
Refrigerant: R600a, 50 grams
Operating temperature: Min and Max rated ambient temperature: +5 °C and +43°C
UIFPF: Grade A.
Vapour Jet Refrigerator And Heat Pump A simple ejector performs the expansion and compression processes involved in the combined cycles. A small electric motor drives the pump of the Rankine cycle. The heat source is electrically heated and produces high pressure vapour to drive the ejector.
A bench top example of a Vapour Jet Refrigerator And Heat Pump that is driven by a heat source. The unit operates on a combined Rankine and vapour compression refrigeration cycle using a low pressure, non-toxic ozone friendly refrigerant.
Hermetic refrigerant compressors have welded sheet steel housing. The drive motor and refrigerant compressor are fitted in this capsule. The motor compressor is suspended by springs in the capsular housing which minimises the transmission of vibration to the capsule body, thereby reducing noise emission. Unlike open compressors, the refrigerant compressor is directly connected to the drive motor and therefore does not require any floating seal.
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The Oil Return In Refrigeration Systems is of key importance for the service life of the compressor and thus for a secure constant supply of refrigeration. In the vaporised refrigerant the oil remains liquid in the lower parts of the system. This can result in lack of oil in the compressor. To return the oil to the compressor, a minimum velocity must be maintained in the pipes. A small diameter of the rising pipe results in a high velocity and ensures the return of the oil even under partial load. However, at full load the pressure loss increases due to the small diameter. The velocity in the rising pipe depends on the pipe diameter and the refrigerant mass flow. In most compressors some lubrication oil is carried along with the compressed refrigerant. In the liquid refrigerant the oil is dissolved in the refrigerant and is transported without problems. If the velocity in the rising pipe on the intake side of the compressor is too low (partial load), the oil is not returned to the compressor due to its higher density.
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Commercial Refrigeration Unit With Fault Simulation device can be used to train students to master the theoretical knowledge and practice skills of the commercial refrigeration system.
Features:
Selection of cooling stage via solenoid valves
Semi-hermetic piston compressor, air-cooled condenser
Mobile refrigeration unit with normal cooling stage and deep-freezing stage
Individual and parallel operation of the cooling stages possible
All fans are speed-controlled
Cooling stages: insulated chambers with air-cooled evaporators
Built in faults set module.
Absorption refrigeration systems operate using thermal energy. This basic principle is demonstrated in the experimental unit with the example of an ammonia-water solution with the ammonia acting as refrigerant. They use the principle of liquids evaporating already at low temperatures when pressure is reduced. In the evaporator the liquid ammonia evaporates and withdraws heat from the environment. To keep the evaporation pressure low, the ammonia steam in the absorber is absorbed by the water. For this purpose, the high concentration ammonia solution is heated in a generator until the ammonia evaporates again. In the final step, the ammonia steam is cooled in the condenser to the base level, condenses and is returned to the evaporator. The low concentration ammonia solution flows back to the absorber. To maintain the pressure differences in the system, hydrogen is used as an auxiliary gas. In the next step, ammonia is permanently removed from the high concentration ammonia solution to prevent the absorption process from being halted.
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The refrigeration circuitry includes a water cooled condenser complete with isolating valves, manual expansion valve, evaporator, variable area flowmeter for mass flow of refrigerant, filter/drier unit, sight glass and over pressure cut-out for unit protection. The unit is designed to use Tetrafluoroethane as the refrigerant with a twin cylinder reciprocating compressor, belt driven by the variable speed dynamometer.
The evaporator coil is mounted in an electrically stirred water/glycol mixture contained in a thermally insulated, stainless steel tank. The water/ glycol mixture is protected from over temperature conditions by a thermostat should the heater should be left on when the compressor is not circulating refrigerant. Heating of this water/glycol mix is infinitely variable enabling balanced experimental conditions over a wide range of temperatures to be obtained.
Experimental Capabilities:
Determine the Mechanical, Thermodynamic (Isentropic) and Volumetric efficiencies.
Estimate the rate at which heat is transferred to the system from the surrounding environment.
Determine the energy flows and coefficient of performance for given operating instructions.
Operate the refrigeration unit over a range of conditions.
Estimate the Heat Transfer Coefficient.
Compile an energy balance under light load and full load conditions.
Examine the behaviour refrigerating cycle under variable loads and speeds.
The electrical components for the start and operation of a refrigerant compressor are clearly visibly arranged in a transparent showcase and already wired. The capacitor and start-up relay required for the motor are examined. Identifying electrical faults in refrigeration systems requires comprehensive knowledge this knowledge includes the design and operation of the individual electrical components as well as the reading of circuit diagrams. It helps to acquire this knowledge. The simulation of 15 different faults, e.g. coil fracture in the motor, short circuit in the operating capacitor or welded contacts in the start-up relay, is possible. Typical protection devices, such as circuit breaker and automatic fuse, are also arranged clearly visible.
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The unit is similar to the being a bench top mounted unit, and with a mimic of the refrigeration circuit on the front panel. The circuits are arranged within the evaporators to allow for hot gas defrosting. Faults that can be simulated include blockage of pipes, filters, failure of expansion devices, thermostats etc. However the circuit is considerably more complicated including one chamber for chilling and one chamber for frozen produce.
Experimental Capability:
Commercial Refrigeration Trainer principle is similar to the but covers a range of refrigeration faults.
It also covers a range of refrigeration faults include fault on the compressor, fault on the oil separator, fault on the constant pressure regulator, fault initiated by blocked freezer evaporator or liquid line or by restricted freezer liquid line or by blocked drier or by blocked condenser air path or by compressor short cycling, faulty check valve, fault on freezer TEV, refrigerator TEV etc.
The refrigeration trainer can be used as an introduction to the basics of refrigeration circuits including safety & operating switches conveniently built into the electrical circuits with the student assessing the consequences, & building up a diagnosis capability.
Features of Commercial Refrigeration Trainer:
Expansion of refrigerant is possible through a number of different devices such as a regulating valves & capillary tubes of various lengths. Pressure is displayed at two points on the circuit
Faults are cleared by releasing the depressed switches & by opening the hand valves. Adjustment faults may be introduced by setting incorrect values on the Pressure stats on the front panel.
The refrigeration trainer provides additional refrigerant capability, with both chiller & freezer chamber. A defrosting heater is provided driven by hot refrigerant gas. Fault initiation is also included
The training system provides functioning refrigeration circuits utilizing commercial control & components. It provides realistic training in setting up, operating & fault finding in refrigeration systems. The system operates with one of the latest environmentally acceptable refrigerants
A mimic of the refrigerant circuit is provided on the front panel showing the circuit comprising of compressor, condenser & evaporator with an insulated chamber.
The refrigeration trainer is mounted on a wheeled stand due to its weight but at bench top height to provide students with experience in the safety, operation & faults of a refrigeration system
Faults can be initiated by switches set in the control & monitoring circuits
Faults that can be simulated include blockage of pipes filter, failure of expansion devices, thermostats etc Faults are selected by depressing switches & by use of the hand valves.
The test rig comprises of a refrigerating chamber with forced draught evaporator fed by a thermostatic expansion valve, a condensation unit of 250 W; transparent access panel; refrigeration circuit with flow display screen equipped with heat exchanger for subcooling the liquid and the solenoid valve; electric defrost system and control through programmable PLC and timing. Our equipment allows students to visualize and study the process of industrial refrigeration. Despite being a bench top unit, it includes all the essential components of a large scale installation. The unit has been built using modular systems and it can reach a cooling temperature of -30ºC. It includes a drying filter and a liquid storage tank.
Experimental Capability:
Heat transfer and thermal insulation
Coolants
Calculation of thermal loads
Refrigerating chambers and industrial refrigeration
Automatic control and instrumentation
Psychrometric processes (low temperature)
Refrigerator cycles
Steam compression
Standard Refrigeration System Training Device can be used to train students to master the theoretical knowledge and practice skills of the standard refrigeration system.
Structure And Compositions:
Evaporator: tube air-cooled type, transparent chamber, and damper
Compressor: 1/2HP, single phase 220V, control box
Condenser: Air-cooled type, single phase 220V, include transparent glass tube
Accumulator: 1/2HP, transparent glass type
Filter dryer: 3/8 nut clamp type or welding type
Sight glass: Welding type or nut clamp type
Manometer: High pressure, low pressure
Expansion valve: manual expansion valve
Electronic valve: 3/8 nut clamp type or welding type.
For better process monitoring the evaporator and condenser are of transparent design evaporator and condenser with pipe coil
Temperature sensor, power meter, manometer in the refrigeration circuit, flow meter for hot and cold water and refrigerant
Demonstration of the processes in a refrigeration circuit
Safety valves at the evaporator and condenser
Expansion valve in the shape of a float valve
Pressure switch to protect the compressor.
Temperatures and pressures at various points are indicated. Sight glasses are provided to indicate the state of the refrigerant. Basic Refrigeration System is used for demonstration of a normal household refrigerator operation. Individual components are clearly shown.
Experiments:
Observation of pressures and temperatures.
Using a p-h state diagram.
Study of layout and process diagram.
Design and investigation of circuits with electrical components from refrigeration
Electrical components mounted clearly visible and connected on terminal blocks
Experimental unit from the practical series for the training of mechatronics engineers for refrigeration
3 pressure switches, 2 thermostats, 1 solenoid valve, 1 timer, 4 circuit breakers, 5 contactors, 3 relays, 2 capacitors
1 set of cables with wire end ferrules for wiring electrical components on terminal blocks
5 lamps to simulate consumers
Electrical components for the start and operation of the compressor mounted clearly visible
Lab jacks and cables to connect the electrical components
Experimental unit from the practical series for the training of mechatronics engineers for refrigeration
Circuit diagram on the front panel for easy identification of the components
Refrigerant circuit with compressor, receiver, 2 valves and 2 manometers to investigate pressure switches on the delivery and intake sides
Operation of a thermostat
Correct electrical connection of a refrigerant compressor.
Complete refrigeration circuit with open compressor, air-cooled condenser, receiver and air cooling evaporator
Replaceable components: compressor, filter/drier, pressure switch and solenoid valve
Trainer from the practical series for the training of mechatronics engineers for refrigeration
Recommended accessories evacuation equipment.
Service exercises in refrigeration systems
Overall arrangement on robust workbench.
Fundamentals:
Evaporator And Condenser Each Available As Air/Refrigerant Heat Exchanger (Finned Tube Heat Exchanger) And As Water/Refrigerant Heat Exchanger (With Pipe Coil)
Setup Of Simple Refrigeration Circuits With Different Components
Light-Weight Aluminium Frame To Arrange 6 Modules
Modules Fitted With Manual Valves
8 Self-Contained Operational Modules Mounted On A Plate Each
Components connected via hoses.
Refrigeration circuit with compressor, condenser, capacity controller, start-up controller, combined pressure switch and 2 evaporators in insulated chambers
Refrigeration chamber with evaporation pressure controller
Freezing chamber with electric defrost heater and hot gas defrosting
Separate or parallel operation of the chambers via solenoid valves
Simulation of 12 faults
Each chamber with solenoid valve, thermostat, thermostatic expansion valve, fan and heat exchanger for refrigerant supercooling
Investigation of a refrigeration system with refrigeration and freezing chambers
Touch panel pc for fault activation, data acquisition, evaluation and representation in the
Refrigerant R404a
Log p-h diagram
