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

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Liquiphant M/S with electronic insert FEL58 + Nivotester FTL325N
22 Hauser
Use in safety instrumented systems
Device behavior during
operation
Behavior of device during power-up
The behavior of the device during power-up is described in the relevant Operating Instructions
(→  16).
Device behavior in safety function demand mode
Version I
The safety-related output signal consists of a current signal according to the NAMUR interface as per
EN 50227(DIN 19234; NAMUR) or IEC 60947-5-6.
• In the GOOD state, the current at terminal 2 is between 2.2 to 3.5 mA
• In demand mode, or if a fault is detected in the device, this current decreases to 0.6 to 1.0 mA
• In the event of a cable open circuit or similar faults, the current is <0.6 mA
• In the event of a short-circuit or similar faults, the current is >3.5 mA
IEC 60947-5-6 defines ranges in which the switch points may be, see "Figure 3 - Control input of the
switching amplifier" in the standard. Accordingly, the calculation of the safety-related characteristic
values is based on the requirement that the downstream evaluation detects the following currents
(Nivotester FTL325N meets this requirement):
• < 0.05 mA reliably detected as a cable open circuit
• > 6.6 mA reliably detected as a short-circuit
Version II to VI
The safety-related output signal consists of one switching contact per channel:
Channel 1: terminal 4 and 5
For the 3-channel Nivotester, also:
• Channel 2: terminal 22 and 23
• Channel 3: terminal 26 and 27
The switching contacts work with quiescent current safety; they are closed in the GOOD state.
The switching contacts are de-energized in the following situations:
• In demand mode
• If a fault is detected
• If the supply voltage fails
Behavior of device in event of alarms and warnings
The behavior of the device if alarms or warnings occur is described in the relevant Operating
Instructions (→  16).
Device configuration for
safety-related applications
The device configuration may not be changed if SIL operation is in progress.
Recommendation: perform a proof test after configuring to ensure that the safety function is
working correctly.
Liquiphant configuration
L
CAUTION
The permitted contact values of the relays may not be exceeded
‣
The operator must take suitable measures to ensure that the permitted contact values of the
relays (U ≤ 253 V
AC
50/60 Hz, I ≤ 2 A, P ≤ 500 VA at cos φ ≥ 0.7 or U ≤ 40 V
DC
, I ≤ 2 A, P ≤ 80
W) are not exceeded (e.g. current limiter, fuse).
L
CAUTION
The protective function can be impaired
‣
After commissioning the measuring system, changes to the settings can impact the protective
function.