How to connect the potentiometer to the inverter2021

At present, many people use the inverter's external potentiometer to use it. The frequency setting is simple and easy to operate. You can set the frequency just by gently turning the knob of the external potentiometer. So everyone knows how the potentiometer is connected to the inverter? What are the precautions for the use of the external potentiometer of the inverter? Since the instructions of various inverters have different requirements for the resistance and power of the external potentiometer, so when you operate the inverter, how to connect the external potentiometer , The operation should be performed according to the instruction manual of the inverter.

Potentiometer principle

The potentiometer is a resistance element with three lead-out pins whose resistance can be adjusted according to a certain changing law. The potentiometer is usually composed of a resistor and a movable brush. When the brush moves along the resistor body, the resistance value or voltage that has a certain relationship with the displacement is obtained at the output end.

How to connect the potentiometer to the inverter?

First of all, it is recommended to use shielded wires for the wiring between the inverter and the external potentiometer. The distance between the inverter and the external potentiometer should not exceed 2 meters. When it exceeds 2 meters, the quality and wire diameter of the shielded wire should be considered. The thickness between them cannot be small. The voltage drop of the frequency converter can be ignored. If the voltage drop is too large, a single-core copper wire can be used to replace the sound shielded wire. Then the analog output of the inverter is set to the operating frequency, and then its regulator can be converted into a 4-20mA signal and sent to the signal input terminal of the inverter, so that the purpose of controlling the frequency can be achieved. At this time, the frequency of the inverter is set The setting can be set by an external frequency potentiometer. Finally, connect the sliding end of the external potentiometer to the AVI of the voltage input end of the inverter, and connect the other ends to +10V and the common end.

In addition, in theory, the potentiometer can also control two inverters at the same time, but in order to reduce the operating error, it is best to use the digital signal of two current outputs to control the potentiometer. First, set a current value (or the frequency value of the inverter). ) To the potentiometer correspondingly output two identical current values, so as to achieve the purpose of controlling two inverters at the same time. At this time, it is better to change the inverter to current signal control.

Precautions for using external potentiometer of the inverter

1. The resistance of the potentiometer should not be too large. When the inverter is controlled at a long distance, the anti-interference ability of the potentiometer will deteriorate.

2. When the external potentiometer is adjusted frequently during the working process, the operating power of the potentiometer should not be too small. Generally, it is recommended to choose 5 to 10 times the actual power loss.

3. Due to the consideration of whether the internal circuits of the inverter are matched or not, the resistance value of the selected potentiometer is generally better not to exceed 10KΩ.

4. Without knowing the internal circuit of the inverter, the resistance of the potentiometer should not be adjusted too small, because if the resistance is small, it will increase the click of the internal control power supply of the inverter, so we should pay attention to this point. .