Acceptance test method for high and low temperature test chamber

1. Main instruments and test apparatus:

1.1 Anemometer: An anemometer with a detection capability of at least 0.05 m/s

1.2 Thermometer: Resistance platinum, temperature A thermoelectric measuring system composed of a couple or other similar temperature sensors and meeting the following requirements: sensor time constant: 20S~40S; expanded uncertainty of temperature measuring system (K=2): not more than 0.4°C

1.3 Surface thermometer: a measuring system consisting of a platinum resistor or other similar sensors and meeting the following requirements: sensor time constant: 20S~40S; Expanded uncertainty of temperature measurement system (K=2): not more than 1.0°C

2. Test conditions:

2.1 The test is carried out no-load

2.2 When performing the cooling speed test, the ambient temperature should not be higher than 25°C, and the power temperature should not be higher than 25°C.Cooling should not be more than 30°C

3. Temperature test method:

3.1 Location and number of test points

3.1.1 Determine the contents of the test chamber workshop Upper, middle and lower three horizontal test surfaces, called upper, middle and lower, the distance between the upper layer and the upper surface of the studio is 1 /10 of the height of the studio, the middle layer passes through the geometric center of the studio and the bottom layer is 10 mm above the sample holder.

3.1.2 The test points are located on the three test surfaces, the central test point is located at the geometric center of the studio, and the distance between the rest of the test points and the wall of the studio is 1/10 of their respective side lengths, but for studio For test chambers with a volume not exceeding 1 cubic meter, the distance is not less than 50 mm

3.1.3The relationship between the number of test points and the volume of the working room is: when the volume of the working room is not more than 2 cubic meters, the test pointThere are 9 test points; when the volume of the studio is more than 2 cubic meters, the number of test points is 15; when the volume of the studio is more than 50 cubic meters, the number of temperature test points can be increased appropriately

Four, test procedures:

4.1 Within the range adjustable temperature of the test chamber, select the nominal temperature and the nominal temperature When the temperature reaches the test temperature and stabilizes for 2 hours, test the temperature of all the test points once in the first minute in 30 minutes , and measure 30 times in total

5. Data processing and test results:

5.1 Correct the measured temperature data according to the correction value of the intest instrument

5.2 Eliminate suspicious data

5.3 Calculate the data measured in the constant temperature stage with 30 measurements per point The average temperature of the value

5.4 Calculate the temperature gradient: the average temperature value minus the small value of the average temperature

5.5 Calculate the temperature fluctuation and temperature deviation

5.6 The difference between the set value of the test box control instrument and the central test value must match the allowable deviation requirements.

Six, the method of testing the temperature difference between the interior wall of the studio and the workspace:

6.1 The location and quantity of test points

6.1.1 Where is the center of the workspace to arrange a temperature sensor, a surface temperature sensor is placed at the geometric center of the six interior walls of the studio

6.1.2 If there is a leadhole or other device in the center of the interior wall of the studio, the distance between the test point and the wall of the hole or other device should not be less than 100 mm

6.2 Test procedure

6.2.1 In the temperature setting range of the test chamber, select the nominal temperature and the nominal temperature as the test temperature

6.2.2 The temperature at the geometric center of the work space reaches the test temperature and stabilizes for 2 hours. Test the temperature values ​​of all test points once every 2 minutes and measure 5 times in total

6.3 Calculation of test results and evaluation

6.3.1 Correct the temperature value of the test according to the correction value of the test instrument

6.3.2 Calculate the arithmetic mean of the temperature of each test point

6.3. 3 Calculate the percentage of the difference between the studio fairy wall and the temperaturePoint studio thermodynamic ure

7.2 Test procedure

7.2.1 In the adjustable temperature range of the test chamber, select the rated temperature as the specified temperature, and the rated temperature as the specified temperature

7.2.2 Turn on the cold source, lower the test chamber from room temperature to the specified temperature, stabilize for 2 hours, adjust to the specified temperature, and detect when the temperature of the test chamber goes from 10% of the temperature range to 90%; make the test chamber at the specified temperature, stable for 2H, then adjust to the specified temperature, and detect when the temperature of the test chamber drops from 90% to 10% of the temperature range.

7.2.3 Record temperature value every minute during heating or cooling process

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