Inverter selection and use precautions

The frequency converter is not normally used under all circumstances, so it is necessary for the user to have a better understanding of the load, environmental requirements and the frequency converter. It is divided into seven points of attention:

1. Long-term low-speed rotation, because the motor generates heat and the fan cooling capacity is reduced, it is necessary to adopt a method of increasing the reduction ratio or switching to a 6-stage motor to make the motor run near a higher frequency.

2. The installation location of the inverter must meet the requirements of the standard environment, otherwise it may cause malfunction or shorten the service life; the distance between the inverter and the drive motor generally does not exceed 50 meters. If a longer distance is required, the carrier frequency needs to be reduced or increased. The output reactor option is required for normal operation.

3. Load type and inverter selection: The load driven by the motor is different, and the requirements for the inverter are different.

4, fan and water pump is the most common load: the requirements of the inverter is the simplest, as long as the inverter capacity is equal to the motor capacity (air compressor, deep water pump, sediment pump, fast changing music fountain needs to increase capacity) .

5, crane load: This type of load is characterized by a large impact at startup, so the inverter is required to have a certain margin. At the same time, if the elbow is placed under the weight, there will be energy feedback, so use the brake unit or use the common bus method.

6. Uneven load: Some loads are sometimes light and sometimes heavy. At this time, the inverter capacity should be selected according to the heavy load conditions, such as rolling machinery, crushing machinery, mixers, etc.

7. Large inertia load: such as centrifuge, punching machine, rotary kiln of cement plant, such load has large inertia, so it may oscillate when starting, and energy feedback when the motor decelerates. A slightly larger frequency converter should be used to speed up the start-up and avoid oscillation. The brake unit is used to eliminate the feedback energy.