Difference in explosion-proof grade

Explosion proof equipment definition: Electrical equipment that will not cause ignition in the surrounding explosive environment under specified conditions.

divided into two categories

Class I: Electrical equipment underground in coal mines;

Class II: Electrical equipment used in explosive gas environments other than coal mines and underground mines.

Class II can be divided into Class IIA, Class IIB, and Class IIC. Equipment marked as Class IIB can be used under the conditions of Class IIA equipment; IIC is applicable to the usage conditions of IIA and IIB.

Explanation: The IIC mark indicates a higher explosion-proof level, but it does not necessarily indicate the performance of the equipment.

Zui high surface temperature: The highest temperature reached by any component of electrical equipment that may cause ignition in the surrounding explosive environment when operating under unfavorable operating conditions within a specified range. The maximum surface temperature should be lower than the flammable temperature.

For example, if the ignition temperature of explosive gases in an explosion-proof sensor environment is 100 ℃, then the highest surface temperature of any component of the sensor should be below 100 ℃ in the most severe working condition.