Introduction of the Electric Motor Protection Device System Functions

Function of electric motor protection device

Protection function

The electric motor protection device can provide comprehensive protection for the motor, including grounding protection, phase-breaking protection, short-circuit protection, over (light) load protection, unbalanced load protection, block protection, low voltage protection, and overvoltage protection. When the motor is working normally, the protection device displays real-time current and voltage on the LCD screen on the panel. Motor protection devices with communication functions will collect signals and transmit them to the background microcomputer through the bus when the microprocessor is idle. When a fault occurs, the protection device will quickly take action, saving the fault type, time, and motor operating parameters on-site, and then report them to the background monitoring agency through the network.

Online monitoring function

The control room operator can access, modify, and set all kinds of protection data for the protection devices on the background microcomputer. At the same time, online monitoring of motor load and power supply quality can help detect overloads and grounding faults in a timely manner. In addition, the powerful information management function of the background microcomputer can effectively record the model, operating mode, and maintenance history of each motor, providing a reliable basis for ensuring the safe production of the process system and reducing accidents and downtime.

Classification of electric motor protection devices by structural form

Generally, electric motor protection devices can be divided into two types: integrated and split. The former is an independent whole, suitable for installation in fixed cabinets, such as the transformation of old switch cabinets, the motor protection device can be directly fixed on the installation panel through the feeder cable. The latter, with the transformer part and the display part separated, can be placed arbitrarily within a certain range, making it very suitable for the installation of new drawer-type switch cabinets.

In engineering practice, due to the widespread use of new low-voltage drawer-type switch cabinets, the display header has been creatively embedded in the movable panel of the switch drawer. This simplifies the cabinet wiring and facilitates system adjustment, parameter setting, display, and monitoring. The digital display panel also enhances the uniformity and aesthetics of the cabinets, making it easy to see the equipment operation status and fault status in the distribution room, greatly facilitating system inspection, maintenance, and repair.

The new type of electronic product, the electric motor protection device, has been running well and accurately displaying various fault types, effectively preventing motor accidents and saving the company a lot of money. Therefore, the widespread use of intelligent motor protection devices can not only improve the accuracy and scientificity of process control, reduce accident rates, but also play a positive role in enhancing the automation level of electrical control systems and promoting national economic development.