Consideration of the residual error probability to IEC 61508
To calculate the PFH (pr obability of a danger ous failure per hour) of a
safety-related function the PFH values of all components used in this
function must be taken into account.
The probability of a dangerous failure per hour (PFH) is
-10
1.8 x 10
/h (per hour).
The maximum service life (T) is 10 years. The unit meets the r equire-
ments for SIL 3.
Explanation of the abbreviations:
PFH = Probability of a dangerous failure per hour
SIL = Safety integrity level
T = Life time (= service life)
The PFH values of the other components, especially of the AS-i safety
monitor, can be found in the corr esponding documentation.
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