Motor in the production process, often due to improper operation of the motor damage, not only the loss of money, while the production schedule had a greater impact. Therefore, proper use of the frequency converter has a positive effect on the protection of the motor. Easy to electrical inverter in the motor motor protection made the following summary:
1, over-voltage protection
Inverter output voltage detection function, the inverter can automatically adjust the output voltage so that the motor does not withstand over-voltage. The inverter protects the motor even if the output voltage fails to adjust and the output voltage exceeds 110% of the normal voltage.
2, under voltage protection
When the motor voltage is lower than 90% of the normal voltage, inverter protection shutdown.
3, over-current protection
When the motor current exceeds 150% of the rated value for 3 seconds, or rated current of 200% / 10 microseconds, the inverter protects the motor by stopping.
4, lack of protection
Monitor the output voltage, when the output phase loss, the inverter alarm, the inverter after a period of time to protect the motor through the shutdown.
5, underload protection
1, the load suddenly lighten Drag the system in operation, the load suddenly lighten, it means that the work of production machinery had an accident, the inverter immediately stop working.
2, vector control underload protection In the case of vector control mode, the load is too light, will affect the vector control of the results, it should be protected.
6, overload protection
The inverter monitors the motor current. When the motor current exceeds 120% of the rated current for 1 minute, the inverter protects the motor by stopping the motor.
7, ground protection
The inverter is equipped with a special grounding protection circuit, which is generally composed of a ground-protection transformer and a relay. When a one-phase or two-phase grounding occurs, the inverter alarms. Of course, if the user request, we can also be designed to protect downtime immediately after grounding.
8, short circuit protection
After the output of the inverter is short-circuited, it will inevitably cause overcurrent. In 10 microseconds, the inverter will protect the motor through shutdown.
9, pressure gauge break protection
In the constant pressure water supply, air compressor, humidity control and other external PID regulator, when the external pressure gauge disconnected, you can self-detection and protection.
10, stall protection
Stall protection is generally for synchronous motors. For induction motors, the stalling during acceleration must be overcurrent, which is achieved by the drive overcurrent and overload protection. Stall during deceleration can be avoided by setting a safe deceleration time during commissioning.