The national standard GB/T29251-2012 vacuum drying box specifies the specific conditions of use, the specific contents are as follows: First, the environmental conditions Vacuum drying ovens should be used under the following environmental conditions: 1. Indoor use; 2. The temperature is 5 ° C ~ 35 ° C; 3. The maximum relative humidity is 80% when the ambient temperature is lower than 31 °C, and the maximum relative humidity linearly drops to 67% when the ambient temperature is 35 °C; 4. Atmospheric pressure: 80kPa~106kPa; 5. Direct radiation without direct sunlight or other heat sources; 6. Pollution degree 2, no explosive gas, high concentration of dust or corrosive substances around; 7. There is no strong vibration and airflow around. Second, the power supply conditions The power supply for the vacuum oven should meet the following conditions: 1. Rated voltage 220V or 380V, the range of deviation from the rated value: -15%~+10%; 2. The rated frequency is 50Hz, and the range of deviation from the rated value is allowed: ±2%. Third, the load conditions The load of the vacuum box should meet the following conditions: 1. The mass of the load placed in the working volume per square meter should not exceed 80kg; 2. The total volume of the load should not be greater than 1/5 of the working chamber volume. QD Cloudy Inernational Pre Ltd , https://www.qdcloudy.com