Siemens SINUMERIK 840D sl Function Manual page 1732

Detailed description
2.1 Path feedrate F
Spindle speed limitation with G96, G961
For the function "Constant cutting rate", in setting data:
SD43230 $SA_SPIND_MAX_VELO_LIMS
(spindle speed limitation with G96/G961)
and in the part program (for the master spindle) with the programming command LIMS, a
maximum spindle speed can be set.
The most recently changed value (LIMS or SD) is active.
LIMS is effective with G96, G961, G97 and can be specified on up to four speed limitations in
the part program in one block. Spindle number Sn=1, 2, 3, or 4 of the master spindle that is
possible in the particular instance can be programmed in part progam instruction LM[Sn].
Note
When the block is loaded in the main run, all programmed values are transferred to to setting
data SD43230 $SA_SPIND_MAX_VELO_LIMS.
The speed limit set with LIMS remains stored after the control is switched off, depending on
the machine data:
MD10710 PROG_SD_RESET_SAVE_TAB[n] (setting data to be updated)
.
When G96, G961, G97 are reactivated, this spindle speed limitation is also activated.
The maximum permissible spindle speed defined by means of G26 or setting data:
SD43220 $SA_SPIND_MAX_VELO_G26 (maximum spindle speed)
, cannot be exceeded.
In the event of incorrect programming that would cause one of the speed limits (G26 or
SD43220 $SA_SPIND_MAX_VELO_G26) to be exceeded, the "Programmed speed too
high" interface signal (DB31, ... DBX83.1) is set.
In order to ensure smooth rotation with large part diameters, the spindle speed is not
permitted to fall below a minimum level.
This speed is defined using setting data:
SD43210 $SA_SPIND_MIN_VELO_G25 (minimum spindle speed)
and can be set for each gear step with the machine data:
MD35140 $MA_GEAR_STEP_MIN_VELO_LIMIT (minimum velocity of the gear step)
.
The minimum spindle speed can be changed in the part program with G25. In the event of
programming that would mean one of the spindle limits (G25 or SD43220
$SA_SPIND_MAX_VELO_G25) is not reached, the "Set speed too low" interface signal
(DB31, ... DBX83.2) is set.
16
Basic logic functions: Feeds (V1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0