Ex space heater is an essential part of increased safe brushless excitation synchronous motor, whose performance has great effect on service performance and Ex property.

The front door of the explosion-proof electric apparatus switch with the connecting way of the housing is an important factor that affects explosion-pro of performance.

The paper discusses the evolution of the explosion-proof electric apparatus of non-grovernmental enterprises in Wenzhou and their evolution direction in the futher.

The requirements of the explosion-proof enclosure of explosion-proof electric apparatus in explosion-proof test are presented,and the errors may appear in measurement.

The reasons of drewfull of explosion-proof electrical apparatus interior is analyzed and propose preventive measures.

The paper presents the technical status mine explosion-proof electrical apparatus of mine flame-proof type vacuum feed switch,mine flame-proof type with intrinsically safe vacuum electromagnetic stater,mine flame-proof type high voltage vacuum distribution device and mine flame-proof type movable transfermer substation,And it analyzes from parameters,electrical system and the structure.

The technical status mine explosion-proof electrical apparatus of mine falme-proof type vacumm feed switch,mine falme-proof type with intrinsically safe vacuum electromagnetic stater are introduced,and design a kind of intelligent motor protector whice use PLC as control core and include many kinds of protection functions.