Endress+Hauser Proline Prosonic Flow P 500 - Page 27

Proline Prosonic Flow P 500 HART Use in protective systems
Endress+Hauser 27
Average probability of failure and mission time
PFD
avg
for a single-channel system:
SIL2 - 1oo1
2
1
0.003
0.0025
0.002
0.0015
0.001
0.0005
0
0 2 4 6 8 10
PFD
a!"
t
A0042079
 2 Options BA "4-20mA HART", CA "4-20mA HART Ex-i passive" and CC "4-20mA HART Ex-i active"
t Mission time in years
1 PFD
avg
- Average probability of dangerous failure on demand
2 Limit value for average probability of failure
1oo1 Single-channel architecture