Basic parameters and safety knowledge of explosion-proof motors
1. Why use explosion-proof motors?
In some places with explosion hazard, when gas or dust encounters ignition source or high temperature, combustion or explosion will occur. When the motor is running, arcs or sparks may occur. These are strong ignition sources. When encountering explosive dust or gas, an explosion may occur.
2. Classification of explosion-proof motors
Class I: Electrical equipment for coal mines;
Class II: Electrical equipment for other explosive gas atmospheres other than coal mines. Class II electrical equipment can be divided into IIA, IIB and IIC according to the characteristics of explosive gases. Among them, the equipment marked with IIB can be applied to the operating conditions of IIA equipment, and the equipment marked with IIC can be applied to the operating conditions of IIA and IIB equipment.
3. Parameters of explosion-proof motor
(1) The rated voltage, rated current, power, and speed are the same as those marked for ordinary motors. That is, the explosion-proof motor has more explosion-proof signs: Ex
Explosion-proof type + equipment category + (gas group) + temperature group
e.g. flameproof Ex d
(2)  equipment category
Electrical equipment for explosive gas atmospheres is divided into:
 Class I: electrical equipment for underground coal mines;
 Class II: Electrical equipment for other explosive gas atmospheres other than coal mines.​​
 Class II flameproof "d" and intrinsically safe "i" electrical equipment are further divided into IIA, IIB, and IIC.​​
Electrical equipment for combustible dust environment is divided into:
A-type dust-tight equipment; B-type dust-tight equipment; A-type dust-proof equipment; B-type dust-proof equipment