1、 Purpose:

The constant temperature and humidity test chamber is one of the climate simulation testing equipment, suitable for assessing the adaptability of various products or materials, as well as electrical and electronic products such as household appliances, instruments, meters, and components, in high, low, high temperature, and high humidity environments. It can be used for testing by various scientific research institutions and factory and mining center laboratories.

2、 Main technical parameters

Temperature range: -20 ℃ to+150 ℃

Heating rate: 1-3 ℃/min (average throughout the entire process)

Cooling rate: 0.7-1 ℃/min (average throughout the entire process)

Temperature uniformity: ≤ 2 ℃

Humidity range: 20% to 98% RH

Humidity fluctuation: ≤± 1.5% RH

Power supply voltage: 220V 50HZ

Studio size: 400 * 400 * 500mm (W * D * H)

3、 Structural characteristics

This test chamber is made of steel plate for the outer shell and stainless steel for the inner liner. Rear device in the workspace: The upper rear part is equipped with a centrifugal stainless steel impeller, which is lightweight and ensures that there is no shaking during motor operation. There is a heater installed under the impeller, which uses nickel chromium electric heating tubes. During the heating process, the thermal balance speed is fast, ensuring the increase or decrease of the chamber temperature and achieving ideal uniformity of the test room temperature and humidity. There is an evaporator installed under the heater, which is used to absorb the temperature inside the working chamber during low-temperature testing, and then lower the room temperature to meet the required testing requirements. At the bottom of the test chamber, there are components such as a refrigeration unit, evaporative condenser, drying filter, solenoid valve, expansion valve, etc.

On the right side of the test chamber is the electrical control part, which adopts an imported programmable temperature and humidity controller. It is very easy to operate. There is an observation window on the door, and the lighting is installed on the upper part of the observation window of the working room, supplied by the switch on the instrument. There is a stainless steel water tank on the lower edge of the door frame, a temperature sensor in the working room, and a test hole on the left side of the box. The electrical structure of the test chamber is simplified compared to similar products, and the main components have undergone strict quality inspection before installation. It runs reliably for a long time.

4、 Safety precautions

1. To ensure personal safety, the metal casing of this equipment should be reliably grounded;

2. The power supply of the equipment should meet the requirements of the nameplate to ensure that the blowing direction of the condensing fan of the refrigeration unit is forward air and then out air, that is, the outlet air is blown towards the compressor;

3. The parameters of the programmable temperature and humidity controller should not be changed arbitrarily except for normal settings, in order to prevent system control confusion and malfunction;

4. To prevent system misoperation and reduce control accuracy, try to avoid opening doors during the experiment;

5. The lighting inside the box is only for observation purposes and should not be turned on for a long time to avoid affecting control accuracy;

5、 Preparation before installation and operation

1. This equipment should be installed indoors on a well ventilated, non corrosive gas surrounding, and flat ground

On the surface.

2. There should be a gap behind the equipment for observing its operation and maintenance after opening.

3. The equipment should have reliable grounding to ensure safety and effective control of the protective control system.

4. If the test chamber is left unused for a long time, the inner walls of the working chamber and the specimen rack should be cleaned before use.

5. Flammable and explosive materials, as well as volatile substances such as gasoline and alcohol, are strictly prohibited from being placed inside the test chamber.

6、 Equipment operation and testing methods:

1High temperature test:

Method: Power on the instrument, set the desired temperature and humidity to 0; Click on the 'Run' button to confirm and press the 'Start' button.

2Low temperature test:

Power on the instrument, set the required temperature and humidity to 0. Click the instrument run button to confirm and press the "start" button, then press the "cooling" switch.

3Room temperature test:

(1) Method: Press the "Start" button, power on the instrument, set the desired temperature and humidity to any value; Click to run and confirm.

4High temperature and high humidity test:Operation process: Check that all switches are in the off state (i.e. popped up), set the instrument test temperature, humidity, and operate the instrument → Press the "start" button to turn on the system and enter automatic control operation.

5. High temperature and low humidity test:Operation process: Check that all switches are in the off state (i.e. popped up), set the instrument test temperature, humidity, and operate the instrument → press the "start" button to turn on → press the cooling switch to enter automatic control operation of the system.

Special note: When the temperature control effect of the instrument is not very good, excessive overheating occurs, and it stabilizes, control should be carried out

When the accuracy is not high and the deviation is large, the instrument self-tuning function can be activated.

6Program testing:

(1) Method: Power on the instrument, change the fixed value control to program control, and return to the main screen after completion.

Fill in the corresponding program number in program: 1, and click Run to confirm. Press the 'Start' button.

(2) Equipment status: The equipment is working according to the set program time. After the program is completed, the instrument automatically stops running.

7、 Simple fault phenomena and countermeasures