The constant temperature and humidity motor is composed of refrigeration technology system, heating system, control management system, humidity information system, air circulation economy system, sensor network system and so on.

The above system belongs to two aspects: electrical refrigeration and mechanical refrigeration.

The working principles and processes of several major systems are described below.

1, constant temperature and humidity motor refrigeration technology system Refrigeration control system is one of the key core components of constant temperature and humidity machine.

Refrigeration methods are generally mechanical refrigeration and auxiliary liquid nitrogen refrigeration, mechanical refrigeration using steam compression refrigeration, mainly by the compressor, condenser, throttling mechanism and evaporator composition.

If we need to test the low temperature to reach -55 ° C, single-stage refrigeration is difficult to meet the design requirements, so enterprises can generally use constant temperature and humidity machine refrigeration mainly using overlapping refrigeration.

The cold system of constant temperature and humidity mechanism is composed of two parts: high temperature part and low temperature part.

The evaporation of the high-temperature part of the refrigerant absorbs the heat of the low-temperature part of the refrigerant. Evaporation: The evaporation of the low-temperature part of the refrigerant absorbs the heat of the cooled object 1 (the air in the testing machine) to obtain the cold capacity.

The high-temperature part and the low-temperature part lead some students to connect through the evaporative condenser, which is both a condenser for the high-temperature part and a condenser for the low-temperature part.

2, heating system: compared with the cooling system, the heating system is relatively simple.

It is mainly composed of high-power resistance wire, because the test requirements for heating rate is relatively large, so the heating system power is relatively large, and the testing machine floor is also equipped with a heater.

3, control system: The control system is the core of the comprehensive laboratory, which determines the temperature rise rate, accuracy and other important indicators of the testing machine.

Most of the controllers of the testing machine are PID control, and a small number of enterprises use a combination of PID and mode 1 paste system control technology.

Because the control system basically belongs to the category of software, and this part of the process of use, generally there will be no problems.

4, humidity control system: the temperature system can be divided into two subsystems: humidification and dehumidification.

The humidification method is generally steam humidification, that is, low pressure steam is directly injected into the test space for humidification.

The humidification method of the invention has strong humidification ability, fast speed and sensitive humidification control, and is easy to realize forced humidification during refrigeration.

1 There are two dehumidification methods: mechanical cooling dehumidification and dry dehumidification.

The dehumidification working principle of mechanical refrigeration dehumidification is to cool the air to below the dew point temperature, so that the moisture content is significantly greater than the saturation of water vapor condensation and precipitation, so that the ambient humidity can be reduced.

Dryer dehumidification is the use of air pump to remove the air in the test box, and then inject dry air, in addition, the wet air is sent to the recyclable dryer for drying, and then sent to the test box for repeated dehumidification.

5, sensor information system: the sensor is mainly through the temperature and humidity and sensor.

The main applications of temperature sensors are platinum group and thermocouple.

There are two kinds of humidity measurement research methods: wet and dry bulb thermometer method and solid state electronic information transmission sensor can be directly correlated measurement method.

Due to the low measurement accuracy of wet and dry ball method, the current constant temperature and humidity boxes are gradually using solid sensors instead of wet and dry balls to measure humidity.

6, air supply cycle management system: The design of air supply cycle economy system is generally composed of centrifugal fans and motor driving fan operation.

It provides air circulation to the test machine.