When it comes to motor protection circuit breakers, few people know what it is and what it does, and the specific installation location is unclear. So in order to solve everyone’s questions, today shendian will tell you the principle and structure of the motor protection circuit breaker, so that everyone has an understanding of him, and you can quickly get familiar with it next time you need it.
Principles and characteristics
Its operating characteristics are close to the allowable overload characteristics of motor windings. Although the accuracy of the action time of the thermal relay is average, it can realize effective overload protection for the motor.
With the continuous improvement and improvement of structural design, in addition to temperature compensation, it also has phase-failure protection and load imbalance protection functions.
The circuit breaker for motor protection with thermal-magnetic tripping is used for overload protection. The structure and operation principle are the same as thermal relays. After the bimetal thermal element is bent, some directly push the tripping device, and some make the contact connected. , And finally cause the circuit breaker to open. The setting value of the electromagnet is relatively high, and it only works when it is short-circuited.
The principle of the motor protector is simple in structure, small in size, low in price, action characteristics in line with current standards, and reliable in protection, so it is still widely used recently. Especially small-capacity circuit breakers are particularly remarkable.
The electronic over-current relay detects the fault current signal through the internal current transformers of each phase, and the principle of the motor protector is processed by the electronic circuit to execute the corresponding action. The electronic circuit changes flexibly, and the action functions are diverse, which can meet the protection of various types of motors.
The principle of the motor protector is characterized by multiple protection functions. There are three main types: overload protection, overload protection ten-phase protection, and overload protection ten-phase protection reverse phase protection.
Through the above simple description, you can be familiar with the motor protection circuit breaker in the future.
