Vega VEGAFLEX 80 series User Manual

8
4 Safety-related characteristics
VEGAFLEX 80 series • Two-wire 4 … 20 mA/HART
42960-EN-170410
4.3 Characteristics acc. to IEC 61508 for versions
with approval Ex-d-ia/XP-AIS
Parameter Value
Safety Integrity Level SIL2 in single-channel architecture
SIL3 in multiple channel architecture
8)
Hardware fault tolerance HFT = 0
Instrument type Type B
Mode Low demand mode, High demand mode
SFF
> 90 %
MTTR 8 h
MTBF = MTTF + MTTR
9)
0.29 x 10
6
h (33 years)
Diagnostic test interval
10)
< 30 min
Failure rates
λ
S
λ
DD
λ
DU
λ
H
λ
L
λ
AD
λ
AU
11 FIT 2154 FIT 167 FIT 41 FIT 92 FIT 32 FIT 21 FIT
PFD
AVG
0.141 x 10
-2
(T1 = 1 year)
PFD
AVG
0.206 x 10
-2
(T1 = 2 years)
PFD
AVG
0.404 x 10
-2
(T1 = 5 years)
PFH
0.167 x 10
-6
1/h
Proof Test Coverag (PTC)
Test type
11)
Remaining failure rate of danger-
ous undetected failures
PTC
Test 1
20 FIT 88 %
Test 2 4 FIT 98 %
4.4 Characteristics acc. to ISO 13849-1 for
versions with approval Ex-d-ia/XP-AIS
Derived from the safety-related characteristics, the following gures
result according to ISO 13849-1 (safety of machinery):
12)
Parameter Value
MTTFd
46 years
DC 93 %
Performance Level 1.67 x 10
-7
1/h
8)
Homogeneous redundancy possible, because systematic capability SC3.
9)
Including errors outside the safety function.
10)
Time during which all internal diagnoses are carried out at least once.
11)
See section "Proof test".
12)
ISO 13849-1 was not part of the certication of the instrument.

Vega VEGAFLEX 80 series Specifications

General

Brand	Vega
Model	VEGAFLEX 80 series
Category	Transmitter
Language	English