Several methods for setting the frequency of the inverter
The frequency converter setting method can be divided into two categories, one is to use the inverter operation panel for frequency setting, the second is to use The inverter control terminal is used for frequency setting. One type uses the inverter operation panel for frequency setting. The frequency setting can be realized by simply pressing the up and down keys on the panel. This method does not require external wiring, the method is simple, the frequency setting precision is high, and it is a digital frequency setting, which is suitable for the frequency setting of a single inverter. The second type is to use the inverter control terminal for frequency setting, and there are two ways, one is to use the external potentiometer for frequency setting; the second is to use the close-up function of the inverter to control the terminal, use the electric potentiometer for frequency setting . A frequency setting using an external potentiometer has the following advantages: (1) The wiring is simple, and only the three ends of the potentiometer are connected to the voltage input terminal of the frequency converter, and the voltage output is Both the end and the public end are available. (2) The frequency setting is simple and easy to operate. The frequency setting can be performed by simply turning the knob of the external potentiometer. (3) The device is sensitive, and the external potentiometer can be placed at any position according to actual needs for remote operation. However, this method also has the following disadvantages: (1) There is a temperature drift phenomenon, because the resistance value is affected by the temperature, when the external temperature changes, the resistance value changes accordingly, and the frequency is set. The setting will also change. (2) Anti-interference can be low. When there is strong electromagnetic interference around, the induced voltage will appear in the connecting cable of the inverter and the external potentiometer, so that the voltage value input to the inverter 2 will change, which will change the frequency setting value and affect the setting frequency. Stability. (3) The distance of the potentiometer device is subject to certain constraints. In theory, the voltage change at the 2nd end of the inverter is 0-10V, but if the external potentiometer device is too far away, the voltage drop will occur on the connecting cable, and the voltage at the 2nd terminal of the inverter will not reach 10V, thus making the output frequency The set value is not reached.