What are the classifications of three-phase asynchronous motors?

1. Classification according to the structure size of the motor

①Large motors refer to those whose center height of the motor frame is greater than 630mm, or frame size 16 and above. Or the outer diameter of the stator core is greater than 990mm. It is called a large motor.

②Medium-sized motors refer to those whose center height of the motor base is between 355 and 630mm. Or the base of No. 11-15. Or the outer diameter of the stator core is between 560 and 990mm. It is called a medium-sized motor.

③Small motors refer to those whose center height of the motor base is 80-315mm. Or the base of No. 10 or below, or the outer diameter of the stator core is between 125-560mm. It is called a small motor.

Second, according to the motor speed classification

①Constant speed motors include ordinary cage type, special cage type (deep groove type, double cage type, high starting torque type), and winding type.

②A variable speed motor is a motor equipped with a commutator. Generally, a three-phase shunt-excited wound rotor motor (rotor control resistor, rotor control excitation) is used.

③Variable speed motors include pole-changing motors, single-winding multi-speed motors, special cage motors, and slip motors.

3. Classification according to mechanical characteristics

① Ordinary cage-type asynchronous motors are suitable for places with small capacity and small slip changes and constant speed operation. Such as blowers, centrifugal pumps, lathes, and other places with low starting torque and constant load.

②Deep slot cage type is suitable for places with medium capacity and slightly larger starting torque than Jingtong cage type asynchronous motor.

③ Double-cage asynchronous motors are suitable for medium and large cage-type rotor motors. The starting torque is relatively large, but the maximum torque is slightly smaller. It is suitable for constant-speed loads such as conveyor belts, compressors, pulverizers, mixers, and reciprocating pumps that require a large starting torque.

④The special double-cage asynchronous motor is made of high-impedance conductor material. The characteristic is that the starting torque is large, the maximum torque is small, and the slip rate is large. The speed adjustment can be realized. Suitable for punching machines, cutting machines, and other equipment.

⑤Wound rotor asynchronous motors are suitable for places with large starting torque and small starting current, such as conveyor belts, compressors, calendars, and other equipment.

Four, according to the motor protection form classification

① In addition to the necessary supporting structure, the open motor has no special protection for the rotating and live parts.

② The rotating and live parts of the protected motor have necessary mechanical protection, but it does not hinder the ventilation. Its vent protection structure is different. There are the following three types: mesh cover type, drip-proof type, and splash-proof type. The anti-drip type is different from the anti-splash type. The anti-drip type can prevent solids or liquids falling vertically from entering the motor, while the anti-splash type can prevent liquids or solids in any direction within an angle of 1000 from the vertical line from entering the interior of the motor.

③The closed motor casing structure can prevent the free exchange of air inside and outside the casing, but it does not require complete sealing.

④Waterproof motor casing structure can prevent water with a certain pressure from entering the motor.

⑤Watertight type When the motor is submerged in water, the structure of the motor casing can prevent water from entering the inside of the motor.

⑥The submersible motor can operate in water for a long time under the specified water pressure.

⑦ The structure of the flameproof motor casing can prevent the gas explosion inside the motor from being transmitted to the outside of the motor and cause the explosion of flammable gas outside the motor.

5. Classification according to the environment in which the motor is used

It can be divided into ordinary type, damp heat type, dry heat type, marine type, chemical type, plateau type, and outdoor type.