Pepperl+Fuchs KF**-CRG2-Ex1.D Series - Characteristic Safety Values

2017-12
12
Functional Safety KF**-CRG2-(Ex)1.D
Planning
3.4 Characteristic Safety Values
Parameters Characteristic values
Relay contact output Current output
KFD2-CRG2-
(Ex)1.D
KFU8-CRG2-
(Ex)1.D
KFD2-CRG2-
(Ex)1.D
KFU8-CRG2-
(Ex)1.D
Assessment type FMEDA report with proven-in-use assessment
1
1
For the proven-in-use demonstration, sales figures, customer returns and questionnaires filled out by
customers were used which show that no unknown systematic faults are expected. The device is based on a
former device that was evaluated for a proven-in-use statement by exida.com GmbH.
Device type B
Mode of operation Low demand mode or high demand mode
HFT 0
SIL (SC) 2
Safety function Digital output Analog output

s
2
2
The failure rates were adapted to most recent date base values. The edition 1 evaluation is still valid for
existing installations.
165 FIT 213 FIT 137 FIT 177 FIT

dd
2
70 FIT 79 FIT 74 FIT 83 FIT

du
2
114 FIT 108 FIT 90 FIT 81 FIT

no effect
2
164 FIT 194 FIT 151 FIT 178 FIT

no part
2
35.8 FIT 34.4 FIT 35.0 FIT 34.8 FIT

total (safety function)
348 FIT 399 FIT 300 FIT 341 FIT

total (signal path)
548 FIT 628 FIT 486 FIT 554 FIT
SFF
3
3
For the calculation of the values acc. to IEC/EN 61508:2010, the "no effect" values are excluded from the
SFF calculation.
67 % 72 % 70 % 76 %
PTC 99 % 99 % 99 % 99 %
MTBF
4
4
acc. to SN29500. This value includes failures which are not part of the safety function/MTTR = 8 h.
207 years 181 years 234 years 206 years
PFH
1
1.13 x 10
-7
1/h
5
5
For using this proof test interval for the safety application, the usage of more than 10 % of the failure rate for
the safety loop is necessary.
1.08 x 10
-7
1/h
4
9.00 x 10
-8
1/h 8.10 x 10
-8
1/h
PFD
avg
for T
1
= 1 year 4.96 x 10
-4
1/h 4.75 x 10
-4
1/h 3.94 x 10
-4
1/h 3.56 x 10
-4
1/h
PFD
avg
for T
1
= 2 years 9.92 x 10
-4
1/h 9.50 x 10
-4
1/h 7.88 x 10
-4
1/h 7.12 x 10
-4
1/h
PFD
avg
for T
1
= 5 years 2.48 x 10
-3
1/h
4
2.37 x 10
-3
1/h
4
1.97 x 10
-3
1/h
3
1.78 x 10
-3
1/h
3
Reaction time
6
6
Time between fault detection and fault reaction
< 1 s
Table 3.1