How to Control VFD’s Frequency Using a 0–10V or 0–20mA Analog Signal?

Published: November 21, 2025

Analog signals such as 0–10V and 0–20mA are among the most widely used methods to control the output frequency of a Variable Frequency Drive (VFD). They are essential for regulating motor speed, airflow, flow rate, or pressure. This article demonstrates how to control a VFD from 0 Hz to 50 Hz using a signal generator that provides 0–10V or 0–20mA analog signals, with parameter configuration and a demonstration video.

1、Principle Overview

0V or 0mA → 0 Hz
Full scale (10V or 20mA) → 50 Hz

Formula:

Output Frequency = (Input Signal / Full Scale) × Max Frequency

2、Voltage Control (0–10V)

2.1 Wiring

Wiring method:

Signal generator 0–10V → AI1(+) or AI2(+)
Ground → GND
Jumper Cap CN400 → Vin

2.2 Parameter Configuration

P0-03(Main frequency reference setting channel selection)=2(AI1) or 3(AI2)
2. P0-12(Frequency reference upper limit)=50.00Hz
3. P0-14(Frequency reference lower limit)=0.00Hz
4. P4-40(AI1 input mode selection)=0(0.00V to 10V input)

3、Current Control (0–20mA)

3.1 Wiring

Wiring method:

Signal generator 0–20mA → AI1(+)
Ground → GND
Jumper Cap CN400 → Cin

3.2 Parameter Configuration

P0-03(Main frequency reference setting channel selection)=2(AI1)
P0-12(Frequency reference upper limit)=50.00Hz
P0-14(Frequency reference lower limit)=0.00Hz
P4-40(AI1 input mode selection)=1(0.00mA to 20 mA input)

4、Applications

Fan airflow regulation
Pump flow control
Pressure/temperature loops
PLC analog speed control

5、Conclusion

Voltage control (0–10V) is suitable for most basic speed-control applications, while current control (0–20mA) is preferred in industrial environments requiring stronger noise immunity. With the wiring, settings, and demonstration provided, you can easily apply both methods to real automation projects.