Siemens SINUMERIK 840D sl Function Manual page 143

Table 7-6 Explanation of the diagram
Time Explanation
t The position control clock cycle, defined by the following MDs:
1
MD10050 $MN_SYSCLOCK_CYCLE_TIME
MD10060 $MN_POSCTRL_SYSCLOCK_TIME_RATIO
t Monitoring clock cycle, defined by the following MD:
2
for 840D sl
MD10090 $MN_SAFETY_SYSCLOCK_TIME_RATIO
for SINAMICS S120:
r9500 SI Motion monitoring clock cycle (Control Unit)
t Time between an error occurring and a limit value being reached
3
t Time until a limit value violation is detected
4
typical 1 monitoring clock cycle, maximum 1.5 monitoring clock cycles + 1 position controller clock cycle)
(
t Response time required to initiate the configured stop response
5
typical 2 monitoring clock cycles, maximum 2.5 monitoring clock cycles + 1 position controller clock cycle)
(
t Time until the stop response that was initiated starts
6
typical 2 ms, maximum 3 position controller clock cycles + 8 ms)
(STOP A:
typical 2 position controller clock cycles, maximum 2 position controller clock cycles)
(STOP B/C:
typical 2 interpolation clock cycles, maximum 2 interpolation clock cycles + 2 monitoring clock cycles
(STOP D/E:
t Time required to bring the axis to a standstill.
7
This time and thus the residual distance traveled by the axis is determined by the axis design (motor, mass, friction, ...)
and the configured stop response (STOP C is faster than STOP D).
Note
Each axis must be measured during commissioning (start-up) to determine the distance that it travels between the limit switch
being violated and it coming to a standstill.
Configurable SG-specific stop responses
Using the configurable SG-specific stop response, a suitable braking behavior can be set for
every SG stage in-line with the application when the particular speed limit value is exceeded.
For example, when:
SETTING-UP, the SG stage SG2 can be active with the configured stop response STOP C
and
in the AUTOMATIC mode, the SG stage SG4 with the configured stop response STOP D.
Activation
The function is active, if MD / parameter 36961/p9561 $MA_SAFE_VELO_STOP_MODE = 5 /
SI Motion SLS (SG) stop response (Control Unit) = 5.
Setting the configurable SG-specific stop responses
The SG-specific stop responses can be set using the following machine data:
For 840D sl:
MD36963 $MA_SAFE_VELO_STOP_REACTION[n]
Safety Integrated
Function Manual, 12/2017, 6FC5397-4BP40-6BA1
Safety functions integrated in the system/drive
7.5 Safely reduced speed (SG)
143