Classification of brake motor protectors

What types of brake motor protectors are there: Thermal relay, electronic type, intelligent type, thermal protection method, magnetic field temperature detection type.

What types of brake motor protectors are there?

 

1. Thermal relay: Suitable for small-capacity AC motors under good operating conditions without frequent starts or harsh conditions; Due to its low accuracy and unreliable nature, its use is not recommended.

 

2. Electronic type: Detects three-phase current values, sets current values using a potentiometer or code switch. The circuit generally uses an analog method and adopts inverse time-limit or definite operating characteristics. Protection functions include overload, phase loss, and rotor stall. Fault types are indicated by indicator lights, and operating power is displayed by digital electronic tubes.

   

3. Intelligent type: Detects three-phase current values. The protector uses a single-chip microcomputer to achieve intelligent and comprehensive protection of the brake motor, integrating protection, measurement, communication, and display. Current setting uses digital setting, which can be set via the operation panel buttons. Users can modify various parameter settings on-site according to the specific situation of the brake motor; Uses digital tubes as display windows or large-screen LCD displays, supporting multiple communication protocols. It is relatively expensive and used in more important situations; High-voltage motor protection uses intelligent protection devices.

 

4. Thermal protection method: A thermal sensitive element is embedded in the brake motor. It protects based on the temperature of the motor windings, offering good protection; However, when the motor capacity is large, it needs to be combined with current monitoring to avoid a sharp temperature rise when the motor is locked. The lag of the temperature measuring element can lead to damage to the brake motor windings.

 

5. Magnetic field temperature detection type: A magnetic field detection coil and a temperature measuring element are embedded in the brake motor, and protection is performed based on changes in the internal rotating magnetic field and motor temperature. The main functions include overload, stall, phase loss, overheat protection, and wear monitoring. It has comprehensive protection functions, but the disadvantage is that it requires the installation of a magnetic field detection coil and temperature sensor inside the motor.