A1-6 – Yokogawa RAKD User Manual
Page 68
A1-6
IM 01R01B30-00E-E 5th edition February 01, 2013 -00
All Rights Reserved. Copyright © 2003, Rota Yokogawa
Table 3: Summary for RAKD ([V1]) with standard limit switches 7 – Failure rates
Profile 2
Profile 4
Fail Safe Detected (λSD)
0 FIT
0 FIT
Fail Safe Undetected (λSU)
163 FIT
205 FIT
Fail Dangerous Detected (λDD)
4 FIT
19 FIT
Fail Dangerous Undetected (λDU)
101 FIT
147 FIT
SFF
4
62.4%
60.3%
MTBF
375 years
261 years
SIL AC
5
SIL2
SIL2
Safety metrics according to ISO 13849-1
6
:
MTTF
d
(years)
1730
899
DC
6%
15%
Category (CAT)
CAT 1
CAT 1
Performance Level (required)
PL
r
= c
PL
r
= c
Performance Level (calculated)
6.60E-08 1/h
1.27E-07 1/h
T[Proof] = 1 year
T[Proof] = 5 years
T[Proof] = 10 years
PFDAVG = 2.96E-04
PFDAVG = 1.37E-03
PFDAVG = 2.72E-03
Table 4: Summary for RAKD ([V2]) with fail-safe limit switches 3 – Failure rates
Profile 2
Profile 4
Fail Safe Detected (λSD)
0 FIT
0 FIT
Fail Safe Undetected (λSU)
162 FIT
215 FIT
Fail Dangerous Detected (λDD)
4 FIT
19 FIT
Fail Dangerous Undetected (λDU)
84 FIT
139 FIT
SFF
4
66.3%
62.7%
MTBF
399 years
259 years
SIL AC
5
SIL2
SIL2
Safety metrics according to ISO 13849-1
6
:
MTTF
d
(years)
1297
723
DC
5%
12%
Category (CAT)
CAT 1
CAT 1
Performance Level (required)
PL
r
= c
PL
r
= c
Performance Level (calculated)
8.80E-08 1/h
1.58E-07 1/h
T[Proof] = 1 year
T[Proof] = 5 years
T[Proof] = 10 years
PFDAVG = 4.01E-04
PFDAVG = 1.86E-03
PFDAVG = 3.68E-03