following error message with program

I have tuned my z-axis servo and I'm now getting following error messages on direction changes. I have a program that cycles the z-axis up and down. I'm not having these problems as I jog the machine......which is how I tuned it. Is there something different when its running a program? Maybe something to change in the traj planner?

jogging is usually slower the rapids.
linuxcnc uses a sliding scale for follow errors - The faster you go the more error allowed.
So I either you need to tune some more or open your following error settings.

Chris M

From the manual:

MIN_FERROR = 0.010 - This is the value in machine units by which the axis is permitted to deviate from commanded position at very low speeds. If MIN_FERROR is smaller than FERROR, the two produce a ramp of error trip points. You could think of this as a graph where one dimension is speed and the other is permitted following error. As speed increases the amount of following error also increases toward the FERROR value.

FERROR = 1.0 - FERROR is the maximum allowable following error, in machine units. If the difference between commanded and sensed position exceeds this amount, the controller disables servo calculations, sets all the outputs to 0.0, and disables the amplifiers. If MIN_FERROR is present in the .ini file, velocity-proportional following errors are used. Here, the maximum allowable following error is proportional to the speed, with FERROR applying to the rapid rate set by [TRAJ]MAX_VELOCITY, and proportionally smaller following errors for slower speeds. The maximum allowable following error will always be greater than MIN_FERROR. This prevents small following errors for stationary axes from inadvertently aborting motion. Small following errors will always be present due to vibration, etc.