Siemens Sinumerik 840D sl Function Manual page 178

Safety functions integrated in the system/drive
6.8 Safety software cams and safety cam track (SN)
Cam signal synchronization is enabled using the following machine data /
parameters:
for 840D sl:
MD36901 $MA_SAFE_FUNCTION_ENABLE, bit 7
for SINAMICS S120:
p9501 SI Motion enable safety functions (Control Unit), bit 7
The cam SGAs including the hysteresis, but without synchronization are displayed
in the service screen and servo trace.
Hysteresis of cam SGAs
When cam synchronization is activated, cam signals are output with a hysteresis
that takes into account the approach direction (see Fig. 6-19, "Hysteresis of the
cam SGAs"). This helps to prevent the SGAs from "flickering" if the axis is
positioned exactly on the cam.
The magnitude of the hysteresis is determined by the following data:
for 840D sl:
MD36940 $MA_SAFE_CAM_TOL
(tolerance for safe software cams)
for SINAMICS S120:
p9540 SI Motion SCA (SN) tolerance (Control Unit)
Figure 6-19 Hysteresis of the cam SGAs
If the cam is incorrectly/inadmissibly parameterized, then this is indicated by
Alarm 27033.
6-178
SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) - - 10.2015 Edition
Cam position
SGA = 1
SGA = 0
Tolerance
for safe
cams
© Siemens AG 2015 All Rights Reserved
10/15
s