Construction principle of high and low temperature humidity heat alternating test box

Refrigeration working principle:

The refrigerating cycle uses an inverse card cycle, which consists of two isothermal processes and two adiabatic processes. The process is as follows: the refrigerant is compressed adiabatically by the compressor to a higher pressure, and the exhausted temperature is increased by the consumed power. The refrigerant is then isothermally exchanged with the surrounding medium via the condenser to transfer heat to the surrounding medium. After the refrigerant through the shut-off valve adiabatic expansion work, when the refrigerant temperature decreases. Finally, the refrigerant absorbs heat from the higher temperature object isothermally through the evaporator, so that the temperature of the cooled object decreases. This cycle is repeated to achieve cooling. The refrigerating system of this chamber adopts a unit of Freon refrigeration system composed of a French-made Taikang closed compressor. The design of the refrigeration system uses energy-adjustment technology to ensure the normal operation of the refrigeration unit and to effectively adjust the energy consumption and cooling capacity of the refrigeration system so that the refrigeration system is maintained in the best operating condition. Balanced thermostats are used. When the cooling system is continuously operating, the control system controls the output of the heater according to the set temperature point through the PID automatic calculation and output, and eventually achieves a dynamic balance. Mechanical sheet metal structure

The cabinet is processed by CNC machine tools. The model is beautiful, novel, and has no reaction handles. It is easy to operate.

The box body gallbladder is made of imported high-grade stainless steel (SUS304) mirror plate or 304B argon arc welding. The outer shell of the box is sprayed with A3 steel plate.

? The use of microcomputer temperature and humidity controller, temperature and humidity control is accurate and reliable.

The large observation window with illuminator keeps the inside of the box bright and multi-layer glass is used to clearly observe the conditions inside the box at any time.

Independent temperature limit alarm system is provided, and the temperature is automatically interrupted when the temperature is exceeded. This ensures that the experiment runs safely without accidents.

? Optional recorder, the printer can print record set parameters and scan out the temperature and humidity curve, 4 ~ 20mA standard signal.

The left side of the box is equipped with a test hole with a diameter of 50mm. Host performance index

Temperature range RT+10°C~100°C

Humidity range 80~98%R•H

Fluctuating/uniformity ≤±0.5°C/±2°C

Temperature deviation +2%, -3%R•H

Heating time room temperature ~ 100 °C about 20min

Cooling time room temperature ~ 100 °C about 20min

Temperature and humidity control system performance indicators

? Controller imported microcomputer wet temperature integrated controller (temperature directly shows the percentage)

Accuracy range setting accuracy: temperature ± 0.1 °C, humidity ± 0.1% R • H,

Indication accuracy: temperature ± 0.1°C, temperature ± 0.1% R•H

Temperature and humidity sensor platinum thermal resistance • PT100Ω

Heating system completely independent system, Nichrome electric heating heater

Humidification system external isolation, all stainless steel boiler superficial evaporative humidifier

Circulation system temperature and low noise air conditioning type motor, multi-blade centrifugal wind wheel

Equipment structure

(1) The chamber of the test chamber is in the form of an integral structure. The refrigeration system is located in the lower part of the cabinet and the control system is located in the upper part of the chamber.

(2) Within the air duct at one end of the studio, distributed heaters, refrigerating evaporators, fan blades, etc.; 试验50 cable holes on the left side of the test box; single-opening test box (stainless steel embedded door handle)

(3) Double-layer high temperature and anti-aging silicone rubber seal can effectively guarantee the temperature of the test chamber.

(4) There are observation windows, frost protection devices and switchable control lights on the door. The observation window is made of multi-layered hollow tempered glass, and the inner bonded sheet type conductive film is heated and defrosted. The lighting adopts the imported brand Philips lamp tube, which can effectively observe the test changes in the working room.