The motor is mainly composed of a magnetic conductive material (silicon steel sheet), a coil winding (copper wire), and a housing shell component. Its working principle is the law of electromagnetic induction in physics. When mechanical energy is converted into electrical energy, it is called a generator. On the contrary, the conversion of electrical energy into mechanical energy is the electric motor, which is what people usually call. The electric motor is divided into a DC motor and an AC motor according to different power supply sources. AC motors are further divided into single-phase and three-phase asynchronous motors. Three-phase asynchronous motor is the leading product of small and medium-sized motors. As one of the most important power equipment, it converts electrical energy into mechanical energy and drives various mechanical equipment. It is widely used in chemical, textile, metallurgy, construction, agricultural machinery, mining, light industry. And other industries, a large number of main mechanical drive power sources such as fans, pumps, compressors, machine tools, printing machines, paper machines, textile machines, rolling mills, air conditioners, urban subways, light rail transit and mining electric vehicles, annual electricity consumption It accounts for more than 60% of the country's total power generation. Therefore, it is an electromechanical product with a large output and a wide range of support. It has an extremely close relationship and important influence on various fields such as national economy, energy conservation and environmental protection, and people's lives. Lack and irreplaceable role. Electric motors are extremely closely related to energy conservation, environmental protection and people's lives, and play an important role in our daily lives. Proper selection of the motor is directly related to the safety of the person and the reliable operation of the equipment. The general requirements for selecting a three-phase asynchronous motor are as follows:
1. Select the rated voltage and power of the motor according to the existing power supply mode and capacity.
a. At present, the frequency of China's power supply grid is 50Hz, the main commonly used voltage levels are 110V, 220V, 380V, 660V, 1000 (1140V), 3000V, 6000V, 10000V.
b. In addition to meeting the mechanical load requirements of the drag, the motor power selection should also consider whether there is a sufficient power supply network. 2, motor type selection
The choice of motor type is related to the requirements of use, environmental pollution at the operating site and climatic conditions.
3, the shell protection level
The selection of the degree of protection of the enclosure directly relates to personal safety and reliable operation of the equipment. It should be protected against human body touching dangerous parts inside the motor according to the use of the motor to prevent solid foreign matter from entering the casing and preventing harmful effects of water entering the casing. The motor enclosure protection level consists of the letter IP plus two characteristic digits. The first characteristic number indicates anti-solid, and the second characteristic number indicates anti-liquid.
4, the installation structure
The appropriate motor installation type should be selected according to the installation requirements of the supporting equipment. The installation type adopts the code IM as the international unified labeling form. The uppercase letters represent horizontal installations as B or vertical installations as V, along with one or two digits of Arabic numerals to indicate structural features and type patterns. Generally, the horizontally mounted motor is IMB3, that is, two end caps, and the organic bottom, the bottom leg, and the shaft extension are mounted on the base member.
