According to its role in the circuit 1. Control electrical appliances: including contactors, switchgear, control relays, main electrical appliances, etc. It plays a major role in control and conversion in the circuit. 2. Protection electrical appliances: including fuses, thermal relays, overcurrent relays, undervoltage relay overvoltage relays, etc., which play a protective role in the circuit. Classified by action principle (1) Appliances that operate manually by hand or rely on mechanical force, such as manual switches, control buttons, travel switches, and other main electrical appliances. (2) Electrical appliances that are automatically operated by means of electromagnetic force or a change in physical quantity, such as contactors, various types of relays, solenoid valves, and the like. Classified by purpose (1) Control appliances are used in various control circuits and control system appliances, such as contactors, relays, motor starters, and the like. (2) The main electrical appliance is used in the automatic control system to send action instructions, such as buttons, travel switches, universal transfer switches, etc. (3) Electrical appliances used to protect electrical circuits and electrical equipment, such as fuses, thermal relays, various protective relays, lightning arresters, etc. (4) Execution electrical appliances refer to electrical appliances used to perform certain actions or transmission functions, such as electromagnets, electromagnetic clutches, etc. (5) Electrical appliances used for distribution and distribution of electrical energy, such as high-voltage circuit breakers, isolating switches, knife switches, automatic air switches, etc. Classified by working principle 1) Electromagnetic appliances work according to the principle of electromagnetic induction, such as contactors, various types of electromagnetic relays, etc. 2) Non-electrical control appliances that rely on external forces or certain non-electrical physical quantities to change, such as knife switches, travel switches, buttons, speed relays, temperature relays, etc. Yoga Bags,Yoga Mat Bag,Yoga Mat Tote Storage Bag,Yoga Gym Bag Dongguan C.Y. RedApple Industrial Limited , https://www.hpgbags.com