1. The altitude is not higher than 2500 meters;
2. The ambient temperature is -25℃-50℃;
3. The air humidity does not exceed 50% at 40℃, and does not exceed 90% at 20℃;
4. There is no corrosive gas in the surrounding environment , No conductive dust, no flammable and explosive media exist;

1. Altitude: no higher than 2500 meters;
2. Ambient temperature: -25°C-50°C;
3. Air humidity: no more than 50% at 40°C, no more than 90% at 20°C;
4. Surrounding environment: No corrosive gas, no conductive dust, no flammable and explosive media;

Ambient temperature: -45-55℃;
working voltage: AC38OV±20%;
voltage measurement accuracy: 0.5 grade;
power factor: ±0.01

1. The altitude is not higher than 2000 meters.
2. The ambient temperature is -20°C to 45°C.
3. The air humidity does not exceed 50% at 40°C, and does not exceed 90% at 20°C.
4. The surrounding environment has no corrosive gas, no conductive dust, and no flammable and explosive media.