Siemens SINUMERIK 828D Function Manual page 1319

Velocity
The positioning speed is taken from the machine data which is configured depending on the gear stage:
MD35300 $MA_SPIND_POSCTRL_VELO
NC/PLC IS "Spindle speed override"/"Feedrate override" at
DB31, ... DBX17.0=0: DB31, ... DBB19)
as well as:
DB31, ... DBX17.0=1: DB31, ... DBB0
are effective as normal for positioning.
The positioning speed can be changed proportionally through the program instruction OVRA[Sn].
Note
OVRA[Sn] is valid modally. After the gear stage change, a value appropriate for the
machining should be reset.
The part-program instruction FA[Sn] does not change the positioning speed during gear stage change.
acceleration
The acceleration values are determined by the machine data which is configured depending on the gear stage:
MD35200 $MA_GEAR_STEP_SPEEDCTRL_ACCEL
and
MD35210 $MA_GEAR_STEP_POSCTRL_ACCEL
The acceleration can be changed proportionally by programming ACC[Sn].
Note
ACC[Sn] is valid modally. After the gear stage change, a value appropriate for the machining
should be reset.
Speed-dependent acceleration
The "knee­shaped acceleration characteristic" is effective as in positioning with SPOS or FC18.
Jerk
It is currently not possible to limit the change in acceleration.
End of positioning
The transition between the end of the positioning action (DB31, ... DBX84.5)
and the start of oscillation mode (DB31, ... DBX84.6) is defined on
reaching "Exact stop fine" (DB31, ... DB60.7) and the time value entered in machine data:
MD3510 $MA_SPIND_POSIT_DELAY_TIME
.
The determination of the transition condition has an effect firstly on the gear stage change time and secondly on
the accuracy of the approach to the preset gear stage change position.
Basic Functions
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
S1: Spindles
16.4 Configurable gear adaptation
1319