Why choose a frequency conversion air compressor Count the protection of the inverter to the motor

Why choose a frequency conversion air compressor Count the protection of the inverter to the motor

During the production and use of air compressor motors, improper operation often causes damage to the motor, which not only loses money, but also has a greater impact on the production schedule. Therefore, the correct use of the inverter has a positive effect on protecting the motor.

　　The protection of the motor by the inverter in the motor is summarized as follows:

　　1, overvoltage protection

　　The output of the inverter has a voltage detection function, and the inverter can automatically adjust the output voltage so that the motor does not withstand overvoltage. Even when the output voltage adjustment fails and the output voltage exceeds 110% of the normal voltage, the inverter will protect the motor by stopping.

　　2, under voltage protection

　　 When the voltage of the motor is lower than 90% of the normal voltage, the inverter protects and stops.

　　3, overcurrent protection

　　 When the motor current exceeds 150% of the rated value for 3 seconds, or 200% of the rated current for 10 microseconds, the inverter protects the motor by stopping.

　　4, lack of phase protection

　　 Monitor the output voltage. When the output phase is missing, the inverter will give an alarm. After a period of time, the inverter will stop to protect the motor.

　　5, underload protection

　　 The load suddenly becomes lighter. During the operation of the drag system, when the load suddenly becomes lighter, it means that there is an accident in the work of the production machinery and the inverter immediately stops working.

　　 Vector control underload protection In the case of vector control mode, the load is too light, which will affect the vector control calculation result, so it should be protected.

　　6, overload protection

　　 The inverter monitors the motor current. When the motor current exceeds 120% of the rated current per minute, the inverter protects the motor by stopping.

　　7, grounding protection

　　The inverter is equipped with a special grounding protection circuit, which is generally composed of a grounding protection transformer and a relay. When one or two phases are grounded, the inverter will alarm. Of course, if the user requires, we can also design to protect the shutdown immediately after grounding.

　　 8. Short circuit protection

　　 After the inverter output is short-circuited, it will inevitably cause overcurrent, and the inverter will protect the motor by stopping within 10 microseconds.

　　 9. Pressure gauge disconnection protection

　　 When there is external PID adjustment for constant pressure water supply, air compressor, humidity control, etc., when the external pressure gauge is disconnected, self-test and protection can be performed.

　　10, stall protection

　　 Stall protection is generally for synchronous motors. For asynchronous motors, the stall during acceleration must be manifested as overcurrent. The inverter realizes this protection function through overcurrent and overload protection. Stall during deceleration can be avoided by setting a safe deceleration time during commissioning.