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

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Liquiphant M/S with electronic insert FEL58 + Nivotester FTL325N
Hauser 13
Version VI: Liquiphant M/S; 3-channel Nivotester FTL325N
Characteristics as per IEC
61508 Value
Safety function MIN MAX
Example
D S
D S
A0027836
Wiring scheme
A
∆s CH2
CH3
CH1
A Other safety equipment e.g. actuator/safety-related PLC
Δs level control (not SIL)
SIL 2
HFT 0
Device type B
Mode of operation Low demand mode
SFF 85 % 87 %
MTTR 8 h
λ
sd
1)
66 FIT 78 FIT
λ
su
554 FIT
λ
dd
13 FIT
λ
du
113 FIT 100 FIT
PFD
avg
for T
1
= 1 year 4.96 x 10 -4 4.37 x 10 -4
MTBF 153 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.
Useful lifetime of electrical
components
The established failure rates of electrical components apply within the useful lifetime as per
IEC 61508-2:2010 section 7.4.9.5 note 3.
According to DIN EN 61508-2:2011 section 7.4.9.5 national footnote N3, appropriate measures
taken by the manufacturer and operator can extend the useful lifetime.