use Z_PROBE_SPEED instead of HOMING_FEEDRATE_Z to go up for z-probe repetitions #775
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Currently, HOMING_FEEDRATE_Z is used as speed to retract the nozzle/z-probe between multiple probing repetitions.
However, if a vibration sensitive Z probe is used (such as a piezo sensor) on a delta with a fast Z homing feedrate, the short motion can well fall within the Z_JERK limit, causing an inadvertent triggering of the z-probe at the end of the move due to the momentum of the extruder. Repetier will then trigger an error because it reports the Z probe as not having properly untriggered after moving to back to the probe rest position.
I'd suggest doing this move at Z_PROBE_SPEED instead, since the slower feed rate doesn't really matter at such short distances, and Cartesian printers have a slow Z max. speed anyway. Alternatively, another setting could be introduced, but I think this is a viable compromise.