Endress+Hauser Liquiphant M/S, Руководство по функциональной безопасности

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Liquiphant M/S with electronic insert FEL58 + Nivotester FTL325N
Hauser 11
Version V: 3 Liquiphant M/S; 3-channel Nivotester FTL325N; 2oo3 architecture
Characteristics as per IEC
61508 Value
Safety function MIN MAX
Example
Wiring scheme
A
(2oo3)
CH2
CH3
CH1
A Other safety equipment e.g. actuator/safety-related PLC; 2oo3 assessment
SIL 2
HFT 1
Device type B
Mode of operation Low demand mode
SFF 99 %
MTTR 8 h
λ
sd
1)
242 FIT 277 FIT
λ
su
1 448 FIT 1 416 FIT
λ
dd
1 FIT
λ
du
19 FIT 17 FIT
PFD
avg
for T
1
= 1 year 8.13 x -10 -5 7.55 x 10 -5
MTBF 67 years
Diagnostic test interval
2)
≤60 s
Fault reaction time
3)
≤3 s
System reaction time
4)
1 s (covered > free) 0.5 s (free > covered)
PTC test sequence A
5)
92 %
PTC test sequence B
6)
34 % 38 %
PTC test sequence C
7)
- 92 %
1) This value takes into account failure types relevant to the function of the electronic components according
to Siemens SN29500.
2) During this time, all diagnostic functions are executed at least once.
3) Time between error detection and error response.
4) Step response time as per DIN EN 61298-2.
5) Proof test coverage when the level is approached, or when the sensor is removed and the tines are
immersed in a medium of similar density and viscosity.
6) Proof test coverage when simulation is performed on the Nivotester or the electronic insert FEL58 by
activating the test button.
7) Proof test coverage when checking the switch point under reference operating conditions.