Siemens Simovert Masterdrives Compendium page 78

Configuration and Connection Examples
Check of the PFH
value of the safety
functions as a whole
2.4.7.2 Supplementary safety function Emergency Stop
Assumption
2-50
Parameter PFH value
ACQUIRE 2.47 x 10
2 x 5.4x10
EVALUATE
4.29 x 10
REACT
Total 8.59 x 10
The requirements regarding PL d with Category 3 for the
protective door safety function are thus fulfilled.
The drive must be safely brought to a standstill and switched off if the
Emergency Stop button is actuated.
The Emergency Stop button is actuated 1x per month.
This safety function can be assessed according to the same principles
described in subsection 2.4.7.1 "Protective door safety function".
However, the Emergency Stop button and the safety switching device
–A1 must be included in the calculation for this safety function. The
position switches for protective door monitoring play no role in the
Emergency Stop function..
Fig. 2-17 Block diagram of the supplementary safety function Emergency Stop
PL Comment
-8
/ h e Position switches –S4 and –S5
-11
/ h Safety switching devices -A2
e and –A3
-8
/ h Switching elements –K1, –K2,
e –K3 and –K4
-8
/ h e < 1x10
6SE7087-6QX70 (Version AM)
Compendium Motion Control
12.2010
-6
/ h
Siemens AG
SIMOVERT MASTERDRIVES