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Normal Working Conditions Of GGJ Low Voltage Switchgear

Apr. 29, 2019

Ambient air temperature of GGJ Low Voltage Switchgear

(1) The upper limit of the ambient air temperature is +40∘C, and the average value within 24h does not exceed +35∘C;

(2) The lower limit of the ambient air temperature is -5 ∘C.


The altitude of the installation site does not exceed 2000m.

Atmospheric conditions

(1) Humidity

The relative humidity of the air at the installation site of Indoor Electrical Switchgear shall not exceed 50% at the highest humidity of +40 °C; higher relative humidity may be allowed at lower temperatures; the minimum monthly minimum temperature of the wettest month shall not exceed +25 °C, The monthly average maximum relative humidity for the month does not exceed 90%. Measures must be taken due to condensation on the product due to temperature changes.

(2) Pollution level

The environmental conditions are graded according to the amount of conductive or hygroscopic dust, free gas or salt and relative humidity, and the frequency of occurrence of surface resistivity degradation events due to moisture absorption or condensation. The pollution level of the surrounding environment is divided into four levels:

Pollution Degree 1: No pollution or only dry, non-conductive pollution.

Pollution Degree 2: In general, there is only non-conductive pollution, but it must be considered that the transient conductivity is caused by condensation.

Pollution Degree 3: Conductive pollution, or dry non-conductive pollution becomes conductive pollution by the expected condensation.

Pollution degree 4: causing persistent conductive pollution, such as pollution caused by conductive dust or rain and snow

GGJ Low Voltage Switchgear