Variable frequency drive speed control

Ahaha, it seems this marine friend’s question regarding the distance control of the positioner is the first time anyone has raised such an issue! Generally speaking, there are basically no distance limitations for speed control using the frequency converter’s controller; only the main power cable coming from the frequency converter has strict distance restrictions! Generally speaking, the speed control positioners we choose usually have an impedance of 1 to 10 kiloohms. The impedance of the control cable used to connect the frequency converter to the field positioner is very low, and can be considered negligible compared to the impedance of the positioner itself. If it doesn’t seem reliable, a locator with a higher impedance can be used; opt for the highest value, 10 kilohms ； At the same time, you can also choose a slightly thicker control cable, 2.5MM2! In short, the distance between the field locator and the frequency converter should not affect the speed control of the frequency converter!

Thank you for your advice, Haiyou. The distance from the control panel to the inverter is about 70 meters, so it’s a bit risky to use potentiometers for speed control; the main factors affecting this are the 10V voltage drop and interference. I simulated the cable length below; it’s just barely sufficient (using a 1.5 square millimeter shielded wire). ) But it’s also a bit unstable, and it’s hard to say about interference in the field.

Potentiometer-based speed control uses a three-wire connection; it’s sufficient to ensure that the resistance values of the three wires are not very different from one another. In the past we used wires that were several hundred meters long, and that worked just fine as well

As long as the resistance value meets the requirements, it should work fine. I really haven’t tested it specifically. Take a look at the inverter’s instructions; such manuals will explain everything quite clearly