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As the name implies, the motor terminal block is a wiring device used for motor wiring. According to the different wiring modes of the motor, the design of the terminal block is also different. Because the general motor works for a long time, it will generate heat, and the working temperature of the motor is relatively high. Moreover, the motor should meet all kinds of working conditions, and the operating conditions are relatively complex. Therefore, the motor wiring board material should have obvious advantages in temperature resistance, insulation and mechanical properties.

In the past, ceramic materials were generally used to make the terminals, but although the temperature resistance of the terminals made of ceramic materials is superior, its strength is not enough, and the installation and use process is prone to fragmentation. Plastic materials are also used to make motor terminal blocks, but the high temperature resistance of plastic is not good, and the plastic is easy to aging under long-term high temperature, which makes the performance of motor terminal blocks decline. In the past, most of the motor terminal blocks were made of phenolic resin, commonly known as bakelite material. However, bakelite material is more advanced than the former two materials, but the color of bakelite material is monotonous, and the strength is not very good. The emergence of BMC material makes the motor terminal block material develop towards BMC material.

BMC material is often called unsaturated polyester group molding compound in China. The main raw materials are GF (chopped glass fiber), up (unsaturated resin), MD (filler) and various additives, which are fully mixed into a pellet like prepreg. BMC materials were first used in the former West Germany and Britain in 1960s, and then developed greatly in America and Japan in 1970s and 1980s. Due to the excellent electrical performance, mechanical performance, heat resistance and chemical corrosion resistance of BMC material, which not only meets the performance requirements of various motor terminal blocks, but also adapts to the molding process to facilitate the large-scale production of motor terminal blocks, BMC material can replace bakelite material to manufacture motor terminal blocks.