Siemens SINUMERIK 840D Function Manual page 134

V1: Feedrates
5.2 Path feedrate F
DB31, ... DBX83.1 (programmed speed too high)
In order to ensure smooth rotation with large part diameters, the spindle speed is not permitted
to fall below a minimum level.
This speed can be set via the setting data:
SD43210 $SA_SPIND_MIN_VELO_G25 (minimum spindle speed)
and, depending on the gear stage, with the machine data:
MD35140 $MA_GEAR_STEP_MIN_VELO_LIMIT (minimum speed of the gear stage)
.
The minimum spindle speed can be changed in the part program with G25. In the event of
incorrect programming that would cause one of the speed limits (G25 or SD43210
$SA_SPIND_MIN_VELO_G25) to be undershot, the following interface signal is set.
DB31, ... DBX83.2 (speed setpoint too low)
For more information on the spindle-speed limitations, see function description S1: "Spindles",
Section: "S1: Spindles (Page 733)".
Note
The speed limits changed with G25/G26/LIMS in the part program are taken into the setting
data and therefore remain saved after the end of program.
However, if the speed limits changed with G25/G26/LIMS are no longer to apply after the end
of program, the following definitions must be inserted in the GUD block of the machine
manufacturer:
REDEF $SA_SPIND_MIN_VELO_G25 PRLOC
REDEF $SA_SPIND_MAX_VELO_G26 PRLOC
REDEF $SA_SPIND_MAX_VELO_LIMS PRLOC
Master spindle changeover with G96, G961
If the master spindle is switched over when G96, G961 are active, the speed of the former
master spindle is retained. This corresponds to a transition from G96 to G97. The master
spindle newly defined with SETMS executes the "Constant cutting rate" function generated in
this way.
Alarms
Constant cutting rate G96, G961, G962
● If no F value is programmed, alarm 10860 "No feedrate programmed" is output. The alarm
is not generated with G0 blocks.
● Alarm 14800 "Programmed path velocity smaller than or equal to zero" is output while
programming a negative path velocity.
● If, with an active G96, G961 or G962, no transverse axis is defined in the machine data:
MD20100 $MC_DIAMETER_AX_DEF (geometry axis with transverse axis function),
alarm 10870 "No transverse axis defined" is output.
134
Axes and spindles
Function Manual, 06/2019, A5E47437747B AA