High and low temperature damp heat test standard for instrumentation

Instruments and meters are used in a wide range, and the high and low temperature damp heat test function of the constant temperature and humidity test chamber is also suitable for the test of instruments and meters. The specific test standards are mentioned in the national standard GB/T 25480-2010. The content compiled in it is for your reference.

A. High temperature test:

1. Set the temperature of the constant temperature and humidity test chamber to 40°C and 55°C. The temperature change rate in the test box (chamber) shall not exceed 1°C/min on average within 5 minutes.

2. Test time: 16h.

3. Test requirements: Put the packaged parts at room temperature into the test box (chamber) also at room temperature, and the packaged parts remain in the test box (chamber) until the temperature gradually drops to room temperature and then take out. Place at least 24h under normal working conditions, and then check whether the performance of the product meets the requirements of the product standard.

B. Low temperature test:

1. Set the temperature of the constant temperature and humidity test chamber to 40°C, -25°C, +5°. The temperature change rate in the test box (chamber) shall not exceed 1°C/min on average within 5 minutes.

2. Test time: 16h.

3.Test requirements: Put the packaged parts at room temperature into the test box (chamber) also at room temperature, and the packaged parts remain in the test box (chamber) until the temperature gradually drops to room temperature and then take out. Place at least 24h under normal working conditions, and then check whether the performance of the product meets the requirements of the product standard.

C. Damp heat test:

1. Within 3h±30min, raise the temperature in the test box (chamber) to 40℃±2K (or 55℃±2K). During the heating period, the relative humidity should not be lower than 95%, and should not be lower than 90% in the last 15min. Test cycle: 2 cycles, each cycle 24h.

2. The temperature of the test box (chamber) is maintained at 40°C±2K (or 55°C±2K) until the full 12h±30min counted from the start of the temperature rise. During this constant temperature period, except that the relative humidity should be maintained between 90% and 100% for the first 15min and the last 15min, the rest of the time should be maintained at (93±3)%.

3. The cooling stage has the following two changes:

Variation 1: Reduce the temperature from 40℃±2K (or 55℃±2K) to 25℃±3K within 3h~6h. The cooling rate of the first 1.5h should make the temperature drop to 25℃±3K within 3h±15min. The relative humidity should not be lower than 90% in the first 15min, and not lower than 95% in the rest of the time.

Variation 2: Reduce the temperature from 40℃±2K (or 55℃±2K) to 25℃±3K within 3h~6h. The relative humidity should not be lower than 80%.

4. The temperature of the test box (chamber) shall be maintained at 25℃±3K, and the relative humidity shall not be lower than 95%, until the end of the first cycle 24h, and then repeat the second cycle of the test.

5. After the test, take out the package and place it for more than 24 hours under normal working conditions, and then check whether the performance of the product meets the requirements of the product standard.