Hope65 VFD supports Modbus RTU over two-wire RS485. Connect the master device RS485 A/+ to Hope65 485+, and RS485 B/- to Hope65 485-. Use shielded twisted-pair cable, especially for longer distances or noisy industrial panels.
For communication monitoring, match P0-00 baud rate, P0-01 data format, P0-02 local address, and P0-05 Modbus format with the PLC/HMI/PC master. For communication start/stop control, set the VFD command source to communication. For frequency setting through Modbus, set the frequency source to communication.
Use address 2000H to write run/stop/reset commands, address 1000H to write communication frequency, address 3000H to read VFD status, address 8000H to read the active fault code, and U0 monitoring addresses such as 7000H to read operating frequency.
Only trained and qualified electrical or automation personnel should wire, configure, or test Hope65 communication control. A wrong Modbus command can start the motor unexpectedly.
Before touching terminals or wiring, switch off all input power, wait at least 10 minutes, and confirm the VFD has discharged safely. During software testing, keep the machine mechanically safe, unloaded where possible, and ready to stop.
This article explains how to connect and configure RS485 Modbus communication for the Hope65 Series Smart AC Drive / VFD. It is intended for PLC programmers, HMI developers, SCADA engineers, panel builders, machine integrators, and service technicians who want to monitor or control the drive through serial communication.
You can use RS485 Modbus to read operating frequency, set frequency, bus voltage, output current, output voltage, output power, VFD status, and fault code. You can also write commands to run forward, run reverse, jog, stop, decelerate stop, free stop, and fault reset. For safe commissioning, always test read-only monitoring first before enabling write commands.
01 Wire RS485Connect 485+ to A/+ and 485- to B/- using shielded twisted pair. | 02 Match P0 SettingsSet baud rate, data format, slave address, delay, timeout, and standard Modbus mode. | 03 Enable ControlUse F0 command/frequency source settings before writing run or speed commands. |
| Product Series | Slanvert Hope65 Series Smart AC Drive / VFD |
| Communication Port | RS485A / RS485B terminals, also marked as 485+ and 485- on wiring diagrams. |
| Protocol | Modbus RTU over two-wire RS485, half-duplex. |
| Master Devices | PLC, HMI, SCADA, PC software, USB-RS485 converter, RS232-RS485 converter, industrial gateway, or data logger. |
| User Level | Automation engineer, PLC programmer, electrical technician, service engineer, or trained panel builder. |
The Hope65 VFD acts as a Modbus slave device. The PLC, HMI, SCADA, or PC acts as the Modbus master. The master sends a read or write request, and the Hope65 responds if the slave address, baud rate, data format, CRC, and command are valid.
01 Master Device
| → | 02 RS485 Bus
| → | 03 Hope65 Slave
|
04 Read Monitoring
| + | 05 Write Control
| Commissioning Rule: First confirm read-only communication. After stable reading works, enable communication command/frequency source and test write commands at low speed. | |
The Hope65 RS485 port uses two-wire differential communication. The terminal marked 485+ is RS485 A, and the terminal marked 485- is RS485 B. Some PLC/HMI devices label terminals differently, such as A/B, D+/D-, +/-, or RS485+/RS485-. Always confirm the master-device documentation.
| Master Side | Hope65 Side | Purpose | Common Issue |
|---|---|---|---|
| A / D+ / RS485+ | 485+ | Positive differential signal line. | If swapped, communication normally fails or gives timeout. |
| B / D- / RS485- | 485- | Negative differential signal line. | Different manufacturers sometimes reverse A/B labeling; swap once for testing if all settings are confirmed. |
| Shield / drain wire | Panel shield grounding point | Noise protection for communication cable. | Incorrect shield grounding can increase noise or create ground-loop issues. |
The P0 group defines the Hope65 Modbus communication settings. The PLC/HMI/SCADA master must use the same communication format.
| Parameter | Name | Range / Options | Default / Typical Use |
|---|---|---|---|
| P0-00 | Baud rate | 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps | Default value 6 = 19200 bps |
| P0-01 | Data format | 0 = 8-N-2, 1 = 8-E-1, 2 = 8-O-1, 3 = 8-N-1 | Default value 3 = 8-N-1 |
| P0-02 | Local address | 0 = broadcast, 1 to 247 = slave address | Default value 1. Use unique address for each VFD. |
| P0-03 | Response delay | 0 to 20 ms | Default value 2 ms. Increase only if the master requires slower response timing. |
| P0-04 | Communication timeout | 0.0 = invalid, 0.1 to 60.0 s = valid timeout | Default 0. Use timeout if the drive must fault/stop when communication is lost. |
| P0-05 | Modbus communication data format | 0 = non-standard Modbus, 1 = standard Modbus | Default value 1 = standard Modbus |
| P0-06 | Communication current resolution | 0 = 0.01A, 1 = 0.1A | Use according to PLC/HMI display requirement. |
| P0-07 | Communication control command address | 0x0000 to 0xFFFF | Default 2000H |
| P0-08 | Communication frequency setting address | 0x0000 to 0xFFFF | Default 1000H |
| P0-09 | Communication setting frequency mode | 0 = percentage, 1 = direct frequency | Default value 1 = direct frequency, unit 0.01 Hz. |
Higher baud rate gives faster communication, but lower interference tolerance and shorter practical cable distance. For long-distance communication, use shielded twisted pair and consider termination resistance.
| Baud Rate | Recommended Maximum Distance | Use Case |
|---|---|---|
| 2400 bps | Up to 1800 m | Very long cable distance, slower data update acceptable. |
| 4800 bps | Up to 1200 m | Long-distance industrial panel communication. |
| 9600 bps | Up to 800 m | Common stable field setting. |
| 19200 bps | Up to 600 m | Default Hope65 setting; good for short-to-medium industrial networks. |
Wiring and P0 settings are enough for monitoring, but not enough for remote run/stop or frequency control. For the VFD to accept Modbus write commands, the operation command and frequency command source must be set correctly.
| Requirement | Parameter to Check | Expected Setting |
|---|---|---|
| Run/stop by Modbus | F0-21 operation command source | Set to communication command channel. |
| Frequency set by Modbus | F0-02 frequency source | Set to communication frequency source. |
| Direct frequency writing | P0-09 | Set to direct frequency mode if writing Hz value in 0.01 Hz units. |
The following addresses are commonly required for PLC/HMI integration. Use hexadecimal addressing as shown. Some PLC software may require decimal conversion or zero-based address offset adjustment.
| Function | Address | R/W | Data Meaning |
|---|---|---|---|
| Communication control command | 2000H | Write | Run, stop, jog, and reset commands. |
| Communication frequency setting | 1000H | Write | Frequency setting. In direct mode, unit is 0.01 Hz. |
| VFD status word | 3000H | Read | Forward running, reverse running, stop, or fault state. |
| VFD fault code | 8000H | Read | Current fault code value. |
Write the required command value to address 2000H. Confirm that the VFD is set to communication command source before expecting these commands to operate the motor.
| Write Address | Command Value | Command | Use With Caution |
|---|---|---|---|
| 2000H | 0001H | Forward running | Confirm motor direction and machine safety first. |
| 2000H | 0002H | Reverse running | Use only if reverse rotation is mechanically safe. |
| 2000H | 0003H | Forward jogging | Check jog frequency and jog ramp first. |
| 2000H | 0004H | Reverse jogging | Use only if reverse jog is safe. |
| 2000H | 0005H | Free stop | Motor may coast. Not a safety-rated emergency stop. |
| 2000H | 0006H | Deceleration stop | Check deceleration time and braking resistor need. |
| 2000H | 0007H | Fault reset | Do not reset repeatedly without correcting the fault cause. |
Use address 1000H to write communication frequency. When P0-09 is set to direct frequency mode, the value uses 0.01 Hz resolution. For example, 50.00 Hz is written as decimal 5000, which is 1388H in hexadecimal.
| Desired Frequency | Decimal Write Value | Hex Write Value | Write Address |
|---|---|---|---|
| 5.00 Hz | 500 | 01F4H | 1000H |
| 10.00 Hz | 1000 | 03E8H | 1000H |
| 25.00 Hz | 2500 | 09C4H | 1000H |
| 50.00 Hz | 5000 | 1388H | 1000H |
U0 monitoring parameters are useful for HMI/SCADA display. The following addresses are commonly used for live drive status and diagnostics.
| Monitor Item | Address | Unit / Resolution | Typical HMI Display |
|---|---|---|---|
| Operating frequency | 7000H | 0.01 Hz | Actual running frequency |
| Setting frequency | 7001H | 0.01 Hz | Target frequency |
| Bus voltage | 7002H | 0.1 V | DC bus voltage |
| Output voltage | 7003H | 1 V | Motor output voltage |
| Output current | 7004H | 0.01 A or 0.1 A depending P0-06 | Motor current |
| Output power | 7005H | 0.1 kW | Output power |
Use the status word to determine whether the drive is running, stopped, or in fault state. Use the fault-code address to display active fault information on HMI/SCADA.
| Read Address | Returned Value | Meaning | HMI Use |
|---|---|---|---|
| 3000H | 0001H | Forward running | Show “Running Forward”. |
| 3000H | 0002H | Reverse running | Show “Running Reverse”. |
| 3000H | 0003H | VFD stop | Show “Stopped”. |
| 3000H | 0004H | Fault | Show “Fault Active” and read 8000H. |
| 8000H | Fault-code value | Active VFD fault code | Show fault code and link to troubleshooting article. |
| Test Stage | Action | Expected Result | If Failed |
|---|---|---|---|
| Stage 1 | Read 7000H operating frequency. | Valid frequency value received. | Check A/B wiring, slave address, baud, parity, COM port, and CRC mode. |
| Stage 2 | Read 3000H VFD status. | Stopped/running/fault status received. | Check register address format and read function code. |
| Stage 3 | Write 5.00 Hz to 1000H. | Set frequency updates to 5.00 Hz. | Check F0-02, P0-09, write function, and address offset. |
| Stage 4 | Write 0001H to 2000H. | Motor runs forward at low speed. | Check F0-21, fault status, run inhibit, and machine interlock. |
| Stage 5 | Write 0006H to 2000H. | Motor decelerates to stop. | Check stop mode, deceleration time, and communication source state. |
| Problem | Likely Cause | Corrective Action |
|---|---|---|
| No response from VFD | A/B reversed, wrong slave address, wrong baud rate, wrong data format, wrong COM port, or wiring open. | Check 485+/485-, P0-00, P0-01, P0-02, master COM port, and cable continuity. |
| CRC error / intermittent communication | Noise, long cable, high baud rate, poor shielding, or no termination on long network. | Use shielded twisted pair, separate cable route, reduce baud rate, and add 120Ω termination if required. |
| Read works but run command does not work | F0-21 not set to communication command source, write address wrong, or drive is in fault/inhibit state. | Set F0-21 correctly, write to 2000H, check 3000H status and 8000H fault code. |
| Run works but speed does not change | F0-02 not set to communication frequency source, P0-09 scaling mismatch, or frequency write address wrong. | Set F0-02 to communication, check P0-09, and write correct value to 1000H. |
| Works with one VFD but not multiple VFDs | Duplicate slave addresses, star wiring problem, termination issue, or network loading. | Give every VFD a unique P0-02 address and use proper daisy-chain RS485 wiring practice. |
| Communication fails only when motor runs | Motor cable noise coupling into RS485 cable. | Separate RS485 from U/V/W cables, improve shielding, grounding, and cabinet EMC practice. |
To reduce troubleshooting time, share the following information:
Smidnya technical support can help review your RS485 wiring, PLC/HMI communication settings, P0 parameters, register addresses, command source, frequency source, and troubleshooting logs before machine commissioning.