Siemens SINUMERIK 840D Function Manual page 745

Special cases
● Tolerance for spindle speed:
If the machine data setting is:
MD35150 $MA_SPIND_DES_VELO_TOL = 0
the NC/PLC interface signal:
DB31, ... DBX83.5 (spindle in setpoint range)
is always set to 1.
WAITS is terminated as soon as the spindle has reached the setpoint-side target after a
change in speed or direction (M3/M4).
● Missing enable signals:
If the WAITS function waits for the "Spindle in setpoint range" signal in speed control mode
and the spindle stops or fails to rotate because an enable signal (axial feed enable,
controller, pulse enable, etc.) is missing, the block is not terminated until the "Spindle in
setpoint range" signal is active, once enable signals are being received again.
● Response to NC and mode-group stop:
If an NC or mode-group stop is triggered during WAITS, the wait operation is resumed after
the NC start with all the above conditions.
Note
In particular when using spindles across different channels, care should be taken when
programming not to start WAITS too early in one channel, i.e. at a time when the spindle in
the other channel is still rotating at its "old" speed.
In such cases, the "Spindle in setpoint range" signal is activated and WAITS is stopped too
soon.
To prevent this happening, it is strongly recommended to set a WAITM before WAITS.
Feedrate
The positioning speed is configured in the machine data:
MD35300 $MA_SPIND_POSCTRL_VELO (position control switching speed)
The configured positioning speed can be modified by programming or by synchronized actions:
FA[S<n>]=<value>
With:
With FA[S<n>]=0, the configured speed takes effect.
Acceleration
The accelerations are configured in the machine data:
MD35210 $MA_GEAR_STEP_POSCTRL_ACCEL (acceleration in position control mode)
MD35200 $MA_GEAR_STEP_SPEEDCTRL_ACCEL (acceleration in the speed control mode)
The configured dynamic response during positioning can be modified by programming or by
synchronized actions:
ACC[S<n>]=<value>
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA
Spindle number
<n>:
Positioning speed in degrees/min
<value>
:
S1: Spindles
18.2 Operating modes
745