1. The ambient temperature is not higher than + 40 ℃, the average temperature within 24 hours is not higher than + 35 ℃, and the lower limit of ambient air temperature is - 5 ℃.

2. The air shall be clean and the relative humidity shall not exceed 50% when the temperature is + 40 ℃. A higher relative humidity is allowed at a lower temperature, e.g. 90% at + 20 ℃, taking into account the possibility of occasional moderate condensation due to temperature changes.

3. The pollution level is 3.

4. The altitude of the installation site shall not exceed 2000 meters.

5. Vertical installation on the ground. The installation inclination shall not exceed 5 degrees.

6. Places without violent vibration and impact are not enough to corrode switchgear and components.

7. The temperature range of transportation and storage is between - 25 ℃ and + 55 ℃, which can reach + 70 ℃ in a short time (no more than 24 hours).