1
3
0
8
6
3
2
0
1
9
-0
4
26
VAA-2E2A-KE1-S/E2, VAA-2E2A-KE1P-S/E2
Appendix B
7.2
Certificates
Approvals in accordance with EN/IEC 61508 and EN/IEC 62061.
7.3
Probability of Failure on Demand Calculation
To calculate the probability of dangerous failure on demand (PFD) of a safety-related function,
the PFD values for all components used within this function must be taken into consideration. In
the case of dual-channel applications, the AS-Interface safe input module does not significantly
contribute to the PFD or PFH (probability of dangerous failure per hour) of the overall system.
The PFD and PFH values for single-channel application can be found in the data sheet. The
PFD or PFH values of the other components, in particular the safety monitor, can be found in
the relevant documentation.
7.4
Transfer time of the safety-relevant information
The transfer time depends essentially on the monitor. The corresponding documentation and
the switch-off times of the actuators must be observed.
