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 following can be seen:
Synchronization
Duplex clutch
Mechatronics
Pressure reservoir
Differential
Gear wheels
Parking lock
Oil pump and electric motor
Oil cooler.
It uses built-in function generator, digital voltmeter, six high-precision digital frequency meter. and has the extended area to achieve open teaching. Comprehensive Electronic Training Kit is integrated experimental box with digital and analog electronic kit.
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Cube Mould standard reinforced band, 150 mm side.
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Grinding Wheel: CBN Wheel For HSS Drill Bit/SD Wheel for Carbide Drill Bit.
Standard equipment: Twelve collets, Nineteen collets.
Complex re-sharpener of end mill & drill, one machine with two function, easy to use, economical and practical, with no skill requirement to grind.
Single-stage compressor, air-cooled, with fan flywheel, intake filter and pipe unions
Assembly exercise for engineering training
Compressor consisting of piston and cylinder, housing, driving gear, cylinder cover with valves
Complete, disassembled piston compressor with small parts set and 6 assembly jigs in a storage case.
Electrical Program provides for the understanding of circuit reading and knowledge of wiring diagrams. Electrical Program is the basic Electricity Trainer used in training programs. Symbol graphics are screened onto each component with a white acrylic background. Using this Program students gain a foundation in the basic principles of electricity and electronics while getting a "hands on" working knowledge of voltage, current, and resistance through series and parallel circuits.
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OXYGEN PRODUCTION
Provides a continuous, variable flow of concentrated oxygen 93% (±3%) derived from room air, to a maximum rate 8 L/min.
Audible and visual alarms for high temperature and pressure failure.
Power efficiency ≤ 70 W/LPM.
Digital meter that displays cumulative hours of device operation.
Oxygen outlet(s) with 6 mm (¼-inch) barbed fitting.
Contains oxygen monitor to verify concentration.
Equipped with two oxygen outlets each provided with controllable flow meter.
Audible and/or visual alarms for low oxygen concentration (<82%) and power supply failure.
Flowmeter continuously adjustable, with markings of at most 0.5 LPM intervals.
Noise level <60 dB(A).
Flowmeter minimum flow rate of 2 L/min. Lower flow rates may be achieved by a combination of the concentrator and a separately supplied flow splitter.
ELECTRICAL CHARACTERISTICS
Mains power cable to have length ≥ 2.5 m.
Capacity for safe operation from at least ± 10% of rated voltage.
Electrical power requirements to be locally compatible.
230 Volt, 50 Hz, 2.1 amps (110 Volt units available)
Electrical protection by resettable circuit breakers or replaceable fuses.
CASING AND ENVIRONMENT
Case to be hard, to be cleanable with standard hospital cleaning materials.
All user-removable filters are cleanable. Cleaning instructions for filters are included in the instructions for use.
Oxygen outlet to be securely mounted and sheltered.
Whole unit to be movable with four wheels.
The unit includes internally and externally mounted filters for cleaning the air intake.
Speculum, vaginal, self-retaining.
Double blade with a screw mechanism to keep the blades open.
To dilate the vagina to examine the vaginal canal and cervix.
Material: Austenitic steel (non-quenched, non-magnetic steel).
Austenitic steel composition: 16 - 18% chromium; 10 - 14% nickel; 2 - 3% molybdenum.
Blade length: approx. 95 mm.
Blade width: approx. 35 mm.
Reusable.
The product is composed of a transparent wind proof cover, a hanging light aluminum foil ball, an angle indicator, a adjustable distance metal ball and a base. Transparent windshield size: 103mm*55mm*115mm, angle indicator range 0-70 degree, minimum angle: 1 degree, lightweight aluminum foil ball and a metal ball diameter: 20mm, the metal ball can adjust the distance of not less than 20mm. With a handle,the total size:165mm*90mm*135mm.
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It is used to make object vibration and sound production experiment, loudness and volume of sound experiment, object sound transmission experiment and simple telephone.
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The seat is provided with a connecting device and a wiring polarity identification; electrode using carbon rod production, diameter 4mm, length 45mm, the closed room size was 120 mm * 50 mm * 25MM, volume 15ml; discharge nozzle is made of glass, the length of about 50mm, and the connecting hose products using milk hose.
The product is made of transparent polycarbonate material. It is made up of experiment base, electrode, airtight chamber, observation tube, air vent and funnel.
The overall size of the instrument is about 150 mm * 60 mm * 190mm, and the operating voltage of the instrument is DC 12V.
The product is composed of 10 30ML reagent bottle, a pipette ball, 6 100MM plastic petri dish. A 10ML scale Straw, a wooden handle tube clip, a stainless steel tweezers and a medicine spoon, needle anatomy 2, 2 stirring rods, 12 plastic bottle, a slice of 50 suits, 100 slides and coverslips, a mini magnifying glass, a stainless steel scissors, a 5ML pipette and 10 glass dropper, respectively 100ML, 250ML and 1000ML, a 60ML plastic funnel, a 100ML plastic cylinder, 3 plastic beaker, 3 pieces of paper label, an operation the knife and 10 blades, 10 test tubes, a mark pen and -10-110 C red liquid thermometer.
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Densitometer is a compact device that can be used to measure turbidity (in the range of 0.5 to 4.0 McFarland units) of cell suspensions in a variety of life science applications.
This is ideal for determining concentration of cells for fermentation process, detecting the susceptibility of micro-organisms to antibiotics, identifying micro-organisms with various test systems, and measuring optical density at fixed wavelength.
This product features a measurement time of 1 second, a precision of 3%, and small footprint and low-profile design.
Cam mechanisms are used in many areas of technology, such as for valve control in combustion engines. The cam follower can work either as a roller tappet, cup tappet, or trailing lever. The stroke is measured using a mechanical position measurement gauge. A scaled disk indicates the associated angle of rotation. The well-structured instructional material sets out the fundamentals and provides a step-by-step guide through the experiments. The simple experimental set-up permits quick demonstration of the action principle, and can be used to demonstrate the influence of different cam shapes.
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The Liquid Sedimentation Apparatus is designed to study the settling characteristics and particle sizes of suspended solid. The rear panel is translucent with back lighting. Scales are provided on the tubes. Sedimentation rate is observed using a stopwatch. The tubes can be removed for washing, filling or mixing of solid particles. Five transparent glass sediment tubes are mounted vertically on a rigid frame.
Experiments:
Settling rate curve.
Effect of suspension height on sedimentation rates.
Effect of concentration on sedimentation rate.
Effect of particle size distribution.
Effect of flocculent.
The cylindrical boiler is filled with a known quantity of water, then heat is given through the resistance. Heat is supplied to the water in the boiler under steady-volume rather than steady-pressure conditions. The Computerized Marcet Boiler is designed to determine the corresponding temperature and pressure values for wet saturated steam at all pressures ranging from atmospheric up to 17 bar. The liquid gradual evaporation will thus cause pressure - and therefore the saturation temperature - to increase in the boiler enclosed space and the values are visualized on digital indicators. Moreover, the transducers and the dedicated software allow the data acquisition of the main thermodynamics quantities and to obtain as a table or as a graph, the acquired values and the thermodynamic calculated quantities.
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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
