Siemens SINUMERIK 840D sl Function Manual page 161

Safe software cams for endlessly turning rotary axes
For rotary axes with cams, the modulo range (cam actual value range) can be set using the
following machine data/parameters:
for 840D sl:
MD36902 $MA_SAFE_IS_ROT_AX
for SINAMICS S120:
p9502 SI Motion axis type (Control Unit)
for 840D sl:
MD36905 $MA_SAFE_MODULO_RANGE
for SINAMICS S120:
p9505 SI Motion SCA (SN) modulo value (Control Unit)
The cam actual value range should be selected as wide as the modulo display of the safe
actual value.
For rotary axes, the modulo display of safe actual values is selected and parameterized using
the following machine data:
for 840D sl:
MD30300 $MA_IS_ROT_AX
MD30320 $MA_DISPLAY_IS_MODULO
MD30330 $MA_MODULO_RANGE
Limiting the cam positions
When parameterizing the cam positions, the following conditions close to the modulo limits
must be maintained.
When cam synchronization is not active:
● - Mod_Pos + Pos_Tol < SN_Pos < Mod_Pos - Pos_Tol
When cam synchronization is active:
● - Mod_Pos + Pos_Tol + Cam_Tol < SN_Pos < Mod_Pos - Pos_Tol - Cam_Tol
Meanings:
Pos_Tol: Actual value tolerance
MD36942 $MA_SAFE_POS_TOL for 840D sl
p9542 SI Motion actual value comparison tolerance (crosswise) (Control Unit) for SINAMICS
S120
Cam_Tol: Cam tolerance
MD36940 $MA_SAFE_CAM_TOL for 840D sl
p9540 SI Motion SCA (SN) tolerance (Control Unit) for SINAMICS S120
Mod_Pos: lower/upper modulo value:
MD36905 $MA_SAFE_MODULO_RANGE for 840D sl
p9505 SI Motion SCA (SN) modulo value (Control Unit) for SINAMICS S120
SN_Pos: Cam position:
Safety Integrated
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Safety functions integrated in the system/drive
7.8 Safety software cams and safety cam track (SN)
161