Safety-related characteristics – KROHNE H250 M40 Safety V1 EN User Manual
Page 16
7
SAFETY-RELATED CHARACTERISTICS
16
H250 M40
www.krohne.com
02/2012 - 4000904201 MA H250 M40 SIL R01 en
H250/M40/ESK-SE
H250/M40/ESK-SE
H250/M40/ESK-SE
H250/M40/ESK-SE with 4..20 mA current output and welded
welded
welded
welded process connections
H250/M40/HT/ESK-SE
H250/M40/HT/ESK-SE
H250/M40/HT/ESK-SE
H250/M40/HT/ESK-SE with 4..20 mA current output and welded
welded
welded
welded process connections
λ
SD
λ
SU
λ
DD
λ
DU
SFF 2 DC
D
MTBF
SIL AC 3
Stress profile 2
(low stress)
0 FIT
183 FIT
293 FIT
111 FIT
81%
73%
170 years
SIL1
Stress profile 4
(high stress)
0 FIT
211 FIT
307 FIT
147 FIT
78%
68%
151 years
SIL1
T[Proof] 4
1 year
2 years
5 years
PFD
AVG
5
5.37*E-04
1.02*E-03
2.46*E-03
λ
SD
λ
SU
λ
DD
λ
DU
SFF 2 DC
D
MTBF
SIL AC 3
Stress profile 2
(low stress)
0 FIT
193 FIT
293 FIT
131 FIT
78%
69%
163 years
SIL1
Stress profile 4
(high stress)
0 FIT
221 FIT
307 FIT
187 FIT
73%
62%
141 years
SIL1
T[Proof] 4
1 year
2 years
5 years
PFD
AVG
5
6.32*E-04
1.20*E-03
2.90*E-03
2
The number listed is for reference only. The SFF must be determined for the complete
subsystem.
3
SIL AC (architectural constraints) means that the calculated values are within the range
for hardware architectural contraints for the corresponding SIL level.
4
It is assumed that proof testing is performed with a proof test coverage of 99%.
5
The PFD
AVG
was calculated for profile 2 using the Markov modelling. The results must
be considered in combination with PFD
AVG
values of other devices of the Safety
Instrumented Function (SIF) in order to determine suitability for a specific Safety
Integrity Level (SIL)
For SIL1 applications, the PFD
AVG
value needs to be < 10
-1
.
For SIL2 applications, the PFD
AVG
value needs to be < 10
-2
.
MA_H250_M40_SIL2_R01_en_904201_PRT.book Page 16 Thursday, March 1, 2012 10:08 AM