There are two possible cases:

Case 1: The frequency value does not change, but motor speed changes when adjusting potentiometer. The reason for this is that VFD is in a display mode showing a different parameter, such as DC bus voltage, output voltage, output current, etc. To adjust VFD to display frequency value, press the SHIFT key multiple times until LED displays Hz.

Case 2: Neither the frequency value nor motor speed changes when adjusting potentiometer. The possible reasons for this are:

• Incorrect speed reference source setting
• Incorrect potentiometer wiring
• The potentiometer wiring is damaged or connection to control terminal is poor
• The potentiometer value is inappropriate or potentiometer is faulty
• The VFD has reached its current limit due to overload

You should:

• Set speed reference source parameters correctly for your specific VFD model
• Ensure that potentiometer is wired accurately according to provided instructions
• Check potentiometer wiring for any breaks and tighten control terminal connections for good contact
• Use a suitable potentiometer with correct value and ensure it is not damaged
• Contact your VFD supplier for further assistance.