What’s the Motor protection knowledge?

Due to the continuous development of the insulation technology, the design of the motor requires not only increased output, but also requires a reduction in the volume, so that the heat capacity of the new type of motor becomes smaller and smaller, and the overload capacity becomes weaker and weaker; The motor often operates in many ways such as frequent starting, braking, reversing, changing load, etc., and imposes higher requirements on the motor protection device. In addition, the motor has a wider application area and often operates in extremely harsh environments, such as humid, high-temperature, dusty, and corrosive environments. All of this has caused the motor to be more easily damaged, in particular, overload, short circuit, phase loss, brooms and other faults have the highest frequency of occurrence.

The traditional protective device protection effect is not ideal: the traditional motor protection device is mainly based on thermal relay, but the thermal relay has low sensitivity, large error, poor stability and unreliable protection. The same is true, although many devices installed thermal relays, but the phenomenon of motor damage and affect the normal production is still widespread. Reasonably select the motor protection device to achieve both the full use of the motor's overload capacity and avoid damage, thereby improving the reliability and continuity of production of the electric drive system. The specific function selection should comprehensively consider the value of the motor itself, the type of load, the use environment, the degree of importance of the motor main equipment, and whether the motor exit operation will have a serious impact on the production system, and strive to be economically reasonable.

The ideal motor protector is not the most functional, nor the so-called most advanced, but should meet the actual needs of the site, to achieve the unity of economy and reliability, with a high performance to price ratio. According to the actual situation of the site, the type and function of the protector are reasonably selected. At the same time, it is considered that the protector is easy to install, adjust, and use. It is more important to select a high-quality protector.