Vega VEGASWING 66 Safety Manual - page 7
7
4 Safety-related characteristics
VEGASWING 66 • Two-wire (8/16 mA)
45309-EN-130722
4 Safety-related characteristics
4.1 Parameter according to IEC 61508
Parameter
Value
Safety Integrity Level
SIL2 in single-channel architecture
SIL3 in multiple channel architecture
2)
Hardware error tolerance
HFT = 0
Instrument type
Type B
Mode
Low demand mode, High demand mode
SFF
> 90 %
MTTR
8 h
MTBF = MTTF + MTTR
3)
1.25 x 10
6
h (143 years)
Diagnosis test interval
4)
< 120 s
Fault reaction time
5)
< 2 s
Failure rates
λ
S
λ
DD
λ
DU
λ
H
λ
L
λ
AD
λ
AU
0 FIT
307 FIT
29 FIT
3 FIT
81 FIT
11 FIT
8 FIT
PFD
AVG
0.025 x 10
-2
(T1 = 1 year)
PFD
AVG
0.036 x 10
-2
(T1 = 2 years)
PFD
AVG
0.071 x 10
-2
(T1 = 5 years)
PFH
0.029 x 10
-6
1/h
4.2 Figures according to ISO 13849-1
Derived from the safety-related characteristics, there are the following
figuresaccordingtoISO13849-1(machinesafety):
6)
Parameter
Value
MTTFd
265 years
DC
93 %
Performance Level
2.95 x 10
-8
1/h (corresponds to "e")
4.3 Supplementary information
The failure rates of the instrument were determined by an FMEDA
according to IEC 61508. Basis for the calculations are the component
failure rates according to SN 29500.
Determination of the
failure rates
2)
Homogeneous redundancy possible
3)
Including errors outside the safety function
4)
Time during which all internal diagnoses are carried out at least once
5)
Time between the occurrence of the event and the output of a fault signal.
6)
ISO 13849-1 was not part of the certification of the instrument.