It can be used as a teaching material for electrician training in coal mine, or as a teaching material for related majors in secondary vocational schools or as a reference for engineers and technicians. The content * * * is divided into three parts. The first part is the primary electrician, including the basic knowledge of electrician, common electrical instruments, power supply and electrical drive; The middle part is an intermediate electrician, including professional knowledge and common sense such as electrician foundation, electronic technology, power supply and electric tow; The second part is the senior electrician part, including the knowledge of electrician foundation, electronic technology, power supply, electric drive and so on that a senior electrician technician should have.