Spindle not changing rotation on M3 / M4

[cncdrive]

Did you measure the direction signal at the VFD? Is it there?
If it is not then let me know and I will check your settings.
But if it is there then it is a VFD settings issue, the direction input is not configured or not configured properly.

[cncdrive]

Did you measure the actual M4 signal at the VFD?
Never say something like nothing changed, because things always change, cables break, connections loose etc.

[cncdrive]

Ok, I have checked your settings and I doubt that if you used these settings then this ever worked.
You have 3 things configured on port#3 pin 17. The M3, The M4 and the Dir pin of the PWM spindle control.
This ofcourse can't work like that, because the signals are in conflict. You trying control one output from 3 sources.

What is pin is port 3 pin 17 is doing on the VFD? Is it the start signal or is it the direction signal?
If it is the start signal then configure it for M3 and also M4 with same Active low polarity and configure the direction signal to the pin which is connected to the VFD direction control input.
Or if it is the direction signal then configure it as the direction signal only and set the M3 and M4 to the other pin which you using as the start signal. Again, same active low polarity for M3 and M4.

So, whenever you push M3 or M4, because they have the same active low setting in both cases the spindle start signal will be triggered at the VFD. If it has to be active low or high depends on the VFD, if it requires an active low or high signal and if your BOB is and connection is inverting or not. Measure it after making the settings.
So, the VFD got the start signal when you pressing the M3 or the M4 and it will change the direction pin signal depending on if the M3 or the M4 was pressed.
You can reverse the rotation polarity you want for M3 and M4 with the active low setting of the Dir signal.

And the PWM goes out on pin 14. which should be OK, if it's polarity is OK, you can verify that too with measuring at the VFD.

[cncdrive]

It's called multimeter and measurement. Measure the voltage on the VFD inputs where the start, the dir and the analog signal are connecting to the VFD.

[cncdrive]

black wire 2 - LI2 - no assigment - can be used for reverse

If only the LI1 forward is connected and the LI2 is not then how do you think the spindle will change the direction?
What do you think which of the signals you have connected will tell the VFD to change direction?
I mean you have only one analog signal which can only give the speed command and you only have one more signal connected.

The only possible answer to my own questions is if the VFD is configured with the LI1 signal as direction signal and there is no start signal, just the analog, which is by the way is a dangerous setup.
If you really have it wired like how you wrote then simply remove the M3 output pin config and also remove the M4 output pin and just leave the Dir pin in the PWM spindle setting, so the dir will switch the forward high or low depending on M3 or M4. And the analog signal will switch the spindle on.
But again, this setup is dangerous because it is missing the safety start signal and I'm not recommending to do the wiring this way.

[cncdrive]

I don't have a drawing of this unfortunately, but what I advice to do is:

1.) Configure your VFD to input start signal on one input and configure another input to be used as direction signal.
2.) Wire the start signal to the start input and configure both the M3 and M4 relay outputs with that output pin. And configure the active low checkbox according to your VFD's input type, if it needs low or high signal to start. Configure both the M3 and M4 the same way, same active low setting and same pin number.
3.) Wire the direction output to the VFD direction input and configure it as the Dir pin in the PWM spindle settings and set the active low checkbox according to the positive rotation direction you want, you can change to what direction the motor will run with M3 and M4, you can reverse the direction of them using this checkbox.
4.) Wire the analog signal to the analog input and configure it as the spindle PWM pin, so it will be the analog signal.

Also don't forget to common the ground of the VFD's analog and digital input's ground screw terminal(s). Not the PE ground , but the analog and inputs circuits grounds and the HDBB2 powersupply GND (0Volts of the PSU)

This way your system is safer, because there is a need for the start signal and also for the analog signal for the motor to start spinning.
Ofcourse still keep other safety standards and rules and do the wiring carefully, because there is high voltage when you open the deck of a VFD.