7i97 wrong Analog output for Spindle

Hi,

I need a +/- 10v signal for my spindle inverter.
If I specify a speed in Linux CNC, e.g. 750rpm, an incorrect analog value comes from the mesa card.
The max speed is 6000rpm.

10V/6000rpm = 1/600 [v/rpm]

1/600 [v/rpm] * 750rpm = 1.25V.

But I always measure a factor of 2 at the analog output, also 2.5V.
I can transfer the whole thing to all other speeds, so that the analog output is 10V at 3000rpm instead of at 6000rpm. The reversal of the direction of rotation works, depending on the direction of rotation (M03/M04) the analog output is +/- V.

Maybe someone can tell me the error in the configuration.

Regards

What do you get if you set P to 0?

I described the problem in my Hurco thread, but I wasn't sure if I could reach people that way. Maybe someone has a similar problem and finds this thread easier.
I found a similar thread but it doesn't solve my problem.
I only have a Mesa 7i97, hal and ini are attached. I've already used another analog output, same result, so I think the hardware is ok.

@PCW I'll test it later.

Thank you.

Yes this was the problem.
I set P to 0 and the Mesa card give me the right analog output.

I try to set P to 1 and 2 because i want to know what happend.

0-> 1,25V
1->2,5v
2->3,75V

Thank for your fast help.

Yes, if feedback is not working and the only non-zero PID terms are FF0
and P, the PID output with FF0 = 1 will be commanded RPM +P*Error.
Error will be the commanded RPM if the feedback RPM is 0.

This is why you get double the expected output when P=1,
The PID component is trying to do the right thing...