To control Hope65 VFD speed from a potentiometer, wire the potentiometer between 10V and GND, and connect the potentiometer wiper/middle terminal to AI1. Then set the frequency source to AI1 so the VFD uses the analog input as the speed reference.
For a PLC or controller analog output, connect the controller signal to AI1 and the analog common to GND. Set jumper J13 according to the signal type: voltage input for 0–10V, or current input for 0/4–20mA.
If analog speed is unstable, noisy, stuck at 0 Hz, not reaching maximum frequency, or reversed, check J13 jumper position, F0-02 frequency source, AI curve scaling, AI1 filter time, shielded cable, and whether the analog wiring is routed separately from motor and power cables.
Only trained and qualified electrical personnel should wire, modify, inspect, or troubleshoot Hope65 control terminals, power terminals, motor wiring, or panel control circuits.
Before touching terminals or wiring, switch off all input power, wait at least 10 minutes, and confirm that the DC bus voltage has discharged to a safe level. Do not change analog wiring while the VFD or panel is energized.
This article explains how to control the Hope65 Series Smart AC Drive / VFD output frequency using analog speed reference. It covers potentiometer wiring, PLC 0–10V wiring, 0/4–20mA wiring, AI1 jumper selection, frequency-source setting, analog curve scaling, analog filtering, noise prevention, and troubleshooting.
Use this guide when the VFD motor starts but speed does not change from the potentiometer, the analog reference is ignored, speed fluctuates, the motor runs only at minimum or maximum frequency, the PLC analog output does not control the drive, or AI1 is not responding correctly.
01 Wire AI CorrectlyUse 10V, AI1, and GND for potentiometer speed control, or AI1 and GND for PLC analog output. | 02 Set J13Select voltage mode for 0–10V or current mode for 0/4–20mA before testing analog control. | 03 Set F0-02Select AI1 as the main frequency source so the VFD follows the analog speed command. |
| Product Series | Slanvert Hope65 Series Smart AC Drive / VFD |
| Analog Terminals | AI1, AO1, 10V, GND |
| Signal Types | Potentiometer, 0–10V analog voltage, 0–20mA current, 4–20mA current, PLC analog output, process controller output. |
| Typical Applications | Pump speed control, fan speed control, conveyor speed adjustment, mixer speed adjustment, machine speed knob, PLC-controlled frequency reference, process speed trimming. |
| User Level | Qualified electrical technician, panel builder, PLC engineer, machine integrator, maintenance engineer, or automation engineer. |
Analog speed control works only when the physical signal, jumper setting, frequency source, AI scaling, and wiring quality all match. The VFD will not follow the potentiometer or PLC analog signal if any one part is incorrect.
01 Signal Source
| → | 02 AI1 Terminal
| → | 03 Drive Logic
|
04 Frequency Output
| → | 05 Motor Speed
| Main Rule: If the analog signal changes but the motor speed does not change, check F0-02 first. If F0-02 is not set to AI1, the VFD will ignore the AI1 speed signal. | |
| Terminal | Function | Typical Use | Important Note |
|---|---|---|---|
| 10V | +10V reference supply | Potentiometer supply terminal. | Do not use as general-purpose power supply for external devices. |
| AI1 | Analog input terminal | Receives 0–10V or 0/4–20mA speed reference depending on J13. | Can also be configured as a digital input, but then it is not used as normal analog speed input. |
| GND | Analog signal common | Reference ground for AI1 and 10V supply. | Use correct analog common; avoid noisy ground loops. |
| AO1 | Analog output terminal | Feedback signal to PLC, meter, or monitoring device. | AO type is selected using J10: voltage or current output. |
A potentiometer gives manual speed control from a panel knob. This is suitable for simple pumps, fans, conveyors, and machines where the operator manually adjusts the motor speed.
Hope65 Terminals 10V / AI1 / GND
| → | Potentiometer 3-Wire Speed Knob
| → | VFD Frequency AI1 → Output Hz
|
| Wiring rule: Use shielded cable for the potentiometer signal. Keep the cable short and route it separately from motor U/V/W and AC power wiring. | ||||
| Potentiometer Terminal | Connect To | Purpose |
|---|---|---|
| End terminal 1 | 10V | Provides reference voltage to the potentiometer. |
| Middle terminal / wiper | AI1 | Sends variable speed command to the VFD. |
| End terminal 2 | GND | Completes analog reference circuit. |
For PLC or controller analog speed command, connect the analog output signal to AI1 and the analog common/reference to GND.
| PLC / Controller Side | Hope65 Terminal | Important Check |
|---|---|---|
| Analog output + / voltage signal | AI1 | Signal should vary between 0V and 10V according to speed command. |
| Analog common / 0V reference | GND | Common reference must be correct; floating reference causes unstable reading. |
| Cable shield | Panel grounding/shielding point as per panel design | Avoid ground loops; use clean analog routing. |
Current input is commonly used for long-distance industrial signals, process controllers, pressure controllers, flow controllers, and PLC analog outputs. Before using current input, set the AI1 jumper correctly.
| Signal Type | J13 Setting | Scaling Note |
|---|---|---|
| 0–10V | Voltage input | 0V to 10V maps through AI curve settings. |
| 0–20mA | Current input | Current signal is converted internally for analog scaling. |
| 4–20mA | Current input | Set minimum input/scaling carefully so 4mA corresponds to the required minimum speed. |
The Hope65 uses physical jumpers to select analog input and output signal type.
| Jumper | Function | Voltage Setting | Current Setting |
|---|---|---|---|
| J13 AI1 | Selects AI1 input mode. | 0–10V voltage input. | 0–20mA current input. |
| J10 AO1 | Selects AO1 output mode. | 0–10V voltage output. | 0–20mA current output. |
After wiring, set the drive parameters so the VFD actually uses AI1 as the speed reference.
| Parameter / Group | Purpose | Recommended Check |
|---|---|---|
| F0-02 | Main frequency source selection. | Set to AI1 when AI1 must control speed. |
| F0-09 | Maximum frequency. | AI full scale normally maps up to the maximum allowed frequency. |
| F0-11 / F0-12 | Upper and lower frequency limits. | Check when analog signal works but speed is limited. |
| F6-13 | AI curve 1 minimum input. | Use to define low-end analog signal point. |
| F6-14 | AI curve minimum corresponding setting. | Use to define the speed percentage at minimum analog input. |
| F6-15 | AI curve 1 maximum input. | Use to define high-end analog signal point, typically 10.00V for voltage mode. |
| F6-16 | AI curve maximum corresponding setting. | Use to define speed percentage at maximum analog input. |
| F6-17 | AI1 filter time. | Increase carefully if analog speed is noisy or unstable. |
| F6-22 | Potentiometer filter time. | Check if built-in/rotary potentiometer input is used and speed is unstable. |
| F6-23 | AI curve selection. | Select two-point or multi-point curve behavior as required. |
Analog scaling defines how the input signal maps to the output frequency command. The exact values depend on machine requirement.
| Requirement | AI Minimum | AI Maximum | Practical Result |
|---|---|---|---|
| Normal 0–10V control | 0V = 0% | 10V = 100% | Knob or PLC signal controls from minimum to maximum frequency range. |
| Avoid motor running below minimum process speed | 0V = selected minimum speed percentage | 10V = 100% | Even at minimum analog input, the VFD can maintain a required process speed if configured. |
| 4–20mA process control | 4mA = minimum required speed | 20mA = maximum required speed | Useful for pressure, flow, level, or remote controller reference. |
| Reverse / inverted analog behavior | Low input = high percentage | High input = low percentage | Use only when the process specifically requires inverse response. |
Analog signals are weak and can be affected by VFD output switching noise, motor cable noise, contactor coils, relay coils, unshielded wiring, and poor common reference. Good wiring practice is essential for stable speed control.
| Wiring Practice | Recommendation | Issue Prevented |
|---|---|---|
| Cable type | Use shielded cable for AI1 and potentiometer signals. | Speed fluctuation and random analog reading. |
| Cable length | Keep wiring as short as possible and not more than 20 m. | Noise pickup and signal drop. |
| Cable route | Route analog cable separately from input power and U/V/W motor cables. | Unstable speed during motor running. |
| Signal filtering | Use ferrite core or filtering at signal source side if interference is severe. | High-frequency noise entering AI1. |
| Software filtering | Increase F6-17 AI1 filter time carefully when analog signal is disturbed. | Unstable display/set frequency; slower response is the trade-off. |
| Problem | Likely Cause | Corrective Action |
|---|---|---|
| Potentiometer does not change speed | F0-02 not set to AI1, wrong pot wiring, wiper not connected to AI1, or J13 mismatch. | Set F0-02 to AI1, check 10V/AI1/GND wiring, and confirm J13 voltage mode. |
| Speed stays at 0 Hz | No analog voltage/current at AI1, missing GND reference, lower frequency limit, or wrong frequency source. | Measure AI1 signal against GND and check F0-02, F0-11/F0-12, and analog curve settings. |
| Speed jumps or fluctuates | Noise, unshielded cable, long analog wiring, poor grounding, or cable routed with motor cable. | Use shielded cable, separate cable route, check GND, add filtering, and increase F6-17 carefully. |
| Speed reaches maximum too early | AI curve maximum input too low or PLC signal scaling mismatch. | Check F6-15/F6-16 and PLC analog output scaling. |
| Speed never reaches maximum | PLC output not reaching 10V/20mA, upper frequency limit active, or AI curve maximum setting wrong. | Measure actual signal at AI1 and check F0-09, F0-11, F6-15, and F6-16. |
| 4–20mA signal behaves incorrectly | J13 still in voltage mode, current loop wiring wrong, or 4mA minimum not scaled. | Set J13 to current input and configure AI minimum input/scaling correctly. |
| Analog control works at stop but fluctuates when motor runs | Motor cable noise coupling into analog wire. | Separate analog wiring from U/V/W motor cable and use shielded cable with proper grounding practice. |
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Smidnya technical support can help review your potentiometer wiring, PLC analog output, AI1 signal, J13 jumper setting, F0-02 frequency source, AI curve scaling, filter setting, and cable routing before commissioning.