Pairing up Mesa 7i76e with VFD Delta C2000

andypugh wrote: I don't think there is any support for Modbus through a Mesa card (yet).
Most people using Modbus and a VFD use a cheap USB to Modbus adaptor. (and lose hard real-time spindle control, but that's generally OK).
Does this look like it might help?

For 0-10V control, you would connect as any other VFD to the 7i76 VFD control outputs.
Nice picture here (looks to be from a different thread)
forum.linuxcnc.org/27-driver-boards/3537...wiring-to-mesa-7i76e

How good are you with C code?
With the correct bit file the 7i76e's RS422 UART can be exposed. See here for the bitfile:
forum.linuxcnc.org/27-driver-boards/3328...6e-with-uart?start=0

If the VFD interface uses a 4 wire interface, it should be possible to use this to communicate via the 7i76e but you would have to write a component to interface with LinuxCNC. THere are some examples with a gyroscope and some stuff Andy wrote as a generic example but there is no specific modbus code.

Good Luck! It would be a fun project!

I asked about modbus because I had no idea how to control the VFD and I thought this is the way.
In the meantime I have managed to control the vfd with a 0-10v lab power supply and by connecting DCM to FWD or to REV i have managed to change the dirrection of the motor.
For the begining, I would like to control the VFD with the mesa board this way.
If anyone can guide me to some post where it describes what configs I need to add to the HAL and INI files, I would be grateful!

Assuming a 5000 rpm spindle, this should work. Edit the numbers to suit your actual spindle.
The following might be needed, and need to be connected to encoders and suchlike, if you want to perform spindle-synched motion, cpntrol a spindle brake etc

I tried adding these to my hal file and what I've noticed is that when I try to start the spindle in reverse, the RUN led on the vfd, ligts up but the spindle does not start.
I measured the voltage between pins 1 and 3 of TB4 and the voltage is 0.
I tried feeding in a 0-10v signal into the vfd on the wires connected to pins 1 and 3 and the vfd starts at a frequency depending on the voltage.
Any idea why mesa is not outputing a voltage on those pins?
Do I need to add some more settings in the hal file? Or did I understood something wrong?

The 7i76 spindle control section is a digital potentiometer, it needs to be connected exactly like a potentiometer would be connected to the VFD.

Do you have the 7i76 manual and the C2000 manual?

I think you need to connect to (on the VFD) +10V, AVI and ACM.

One thing with my Huanyang:

It works fine with the 7i76e according to newbynobi's diagram., BUT
Just having set a speed and started once you can not simply reverse direction. Motor will stay nevertheless what dir pin does. Solution is in my case a small CL that disable the enable pin fore 100ms on every dir change.

P. S
I need that as I can use z-min sensor for (old fashioned) automatic threading.

I think you are misunderstanding how the analog output works on a 7i76.

It works like a potentiometer. You need to connect a DC voltage source to pins 1 and 3 of TB4 (10v for example). Then pin 2 will output what ever % of the voltage between 1 and 3 as commanded.

Most VFDs will have a voltage source for connecting up such a pot. You would connect that to pin 3. Pin 1 and 2 would connect to the ground and + input on the VFD.

Sorry if I'm asking stupid questions..
I understand that if I would use a potentiometer, I would wire it between +10v/AVI/ACM but how would this translate when trying to connect to the mesa board?
Now I have connected the ACM to pin 1, AVI to pin 3
Where should I wire the +10v/AVI/ACM ?

TB4.1 --> ACM
TB4.2 --> AVI
TB4.3 --> +10V

Thanks, I will try it next time I get to the shop and let you know!