WAGO-I/O-SYSTEM 750
Device Description
37
753-668/000-004 4FAI 0/4-20 mA Diff PROFIsafe
Manual
Version 1.0.0, valid from HW/SW Version 01/01
3.6.7.2
Single-Channel Safety Application
Table 17: Safety Parameters for Single-Channel Safety Application
Maximum safety integrity level per IEC 62061
SIL 2
Maximum safety integrity level per IEC 61508
SIL 2
Maximum performance level per EN ISO 13849-1 Cat. 2/PL d
Proof test interval/usage duration
20 years
Probability of failure
PFD
AVG
*)
,
Proof test interval
20 years (low demand
mode) (IEC 61508)
for 1 input
(input to fieldbus)
4,37
×
10
−
5
for 2 inputs in the same
safety function
(input to fieldbus)
5,88
×
10
−
5
for 4 inputs in the same
safety function
(input to fieldbus)
8,89
×
10
−
5
Probability of failure
PFH
*)
,
Proof test interval
20 years (high demand
mode) (IEC 61508)
for 1 input
(input to fieldbus)
1,3
×
10
−
9
1/h
for 2 inputs in the same
safety function
(input to fieldbus)
1,3
×
10
−
9
1/h
for 4 inputs in the same
safety function
(input to fieldbus)
1,3
×
10
−
9
1/h
Hardware fault tolerance HFT with
single-channel application
(IEC 61508)
0
(1 error in the application can
lead to a failure of the safety
equipment)
DC
AVG
(Diagnostic
Coverage Level)
for 1 input
(input to fieldbus)
97,75 %
for 2 inputs in the
same safety function
(input to fieldbus)
97,82 %
for 4 inputs in the
same safety function
(input to fieldbus)
97,94 %
MTTF
d
(Mean Time To Failure
dangerous)
for 1 input
(input to fieldbus)
698 years
for 2 inputs in the
same safety function
(input to fieldbus)
631 years
for 4 inputs in the
same safety function
(input to fieldbus)
530 years
*)
PFD
AVG
: Probability of a dangerous failure on demand
PFH: Probability of a dangerous failure per hour