[ Vfdmod ] An easy VFD control over MODBUS RTU

Hello everyone!

I wrote my own HAL userspace component - it's called Vfdmod - to control any VFD that supports standard MODBUS RTU transfer mode.

• Sources: github.com/aekhv/vfdmod
• Documentation: github.com/aekhv/vfdmod/wiki
• DEB packages: github.com/aekhv/vfdmod/releases

Features

• Setting command speed with MODBUS function codes 0x06 (write holding register) and 0x10 (write multiple holding registers).
• Setting control word with MODBUS function codes 0x06, 0x10, 0x05 (write coil) and 0x0F (write multiple coils).
• Reading any count of user defined parameters with MODBUS function codes 0x01 and 0x03.
• Four types of user defined parameters are supported: bit, float, s32 and u32.
• Built-in PyVcp generator.
• RS485 connection state monitoring including total error count and last error code.
• Auto reconnection attempts when USB-to-RS485 adapter was physically re-plugged.
• Huanyang VFDs are not supported because they use non-standard MODBUS function codes.

Screenshots




Examples

• Configuration file for Tecorp HC1C+ (low cost chinese VFD):

  [Common]
  MaxSpeedRPM=24000
  MinSpeedRPM=3000
  AtSpeedThreshold=0.01
  
  [RS485]
  SlaveAddress=1
  SerialDevice=/dev/rs485
  BaudRate=19200
  DataBits=8
  Parity=N
  StopBits=1
  
  [Control]
  Address=0x2000
  RunForwardValue=0x000A
  RunReverseValue=0x0006
  FaultResetValue=0x0010
  StopValue=0x0001
  
  [SpindleRpmIn]
  Address=0x2001
  Multiplier=1
  Divider=6
  
  [SpindleRpmOut]
  Address=0x0004
  Multiplier=10
  Divider=1
  
  [Command frequency]
  Address=0x0001
  Multiplier=1
  Divider=10
  PinType=float
  PinName=command-frequency
  
  [Output frequency]
  Address=0x0002
  Multiplier=1
  Divider=10
  PinType=float
  PinName=output-frequency
  
  [Output current]
  Address=0x0003
  Multiplier=1
  Divider=10
  PinType=float
  PinName=output-current
  
  [DC bus voltage]
  Address=0x0005
  Multiplier=1
  Divider=10
  PinType=float
  PinName=dc-bus-voltage
  
  [Temperature]
  Address=0x0006
  Multiplier=1
  Divider=10
  PinType=float
  PinName=temperature

Sounds a lot like Mb2hal. How is your component different/better?

seams onlyinteresting for longtime users to see the state of the VFD
most wont need it as they just use the error channel to stop f somthing happens
but it is good to have it there

What VFD did you test this

Todd wrote:

Sounds a lot like Mb2hal. How is your component different/better?

It's hard to answer because I didn't work with mb2hal

Your new component may be mostly replicating the same function of the pre-existing Mb2hal component. You might want to look into it

Excellent work, could you post your hal file? I have questions about how you control your spindle.

Does this userspace component work with linuxcnc version 2.9?

COFHAL wrote:

Does this userspace component work with linuxcnc version 2.9?

My CNC machine works on LinuxCNC 2.7, so I can test Vfdmod with this version only.

COFHAL wrote:

Excellent work, could you post your hal file? I have questions about how you control your spindle.

Thanks a lot! About HAL file see user guide above or ask free here

I have a problem with the userspace component vdfmod vdfmod. I installed it to control my VDF Fuling DZB280, when I run linuxcnc, the VDF automatically receives the minimum RPM command, in this case 300 RPM, but it is not possible to control the VDF, it cannot RUN, STOP or change frequency. And on the control panel, the RS245 connection LED is always red. When seeing the HAL configuration, I see that all the vdfmod.parameters are connected to the panel but not to any input as it appears in its picture. The same goes for all vdfmod rs485 commands.