Siemens SITRANS LUT400, Operating Instructions Manual

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Page 122 SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS A5E33329501
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Fail-safe and Simulation
When simulating Level or Discrete Inputs, the LUT400 will never enter the Fail-safe state.
Faults that would normally cause a fail-safe condition (such as a broken cable or LOE)
may still occur, but a fail-safe condition will not be reported on the device during
simulation.
HART status
When using HART communications via software tools such as PDM, AMS, FDT, and
FC375/475, the Level value and the readings derived from level will display simulated
values (when level or discrete input simulation is enabled on LUI). (See
Process Variables
within PDM, AMS, FDT, and FC375/475.) Device status conditions within each tool will also
indicate that the device is in simulation mode (see
Diagnostics
).
Simulation process
Simulation is an iterative process whereby parameters are adjusted and corresponding
results are viewed in Measurement Mode. Level and Discrete Inputs can be simulated
separately, or concurrently. When either simulation is enabled, the LCD displays
Simulation Enabled
in the text area for status messages (see
Measurement mode
display: Normal operation
on page 34).
To stop simulation at any time, set the parameter for the function being simulated (
3.4.1.1.
Level Simulation Enable
,
3.4.2.1. Discrete Input 1
,
3.4.2.2. Discrete Input 2
) to Disabled.
In general, to run a simulation:
1. Select the function to be simulated: Level or Discrete Input (can be simulated
concurrently).
2. Set simulation parameters if performing a Level simulation.
3. Decide if pumps will be active during simulation (see
Pump relay behaviour during
simulation
on page 121).
4. Start simulation.
Simulating a fixed level
1. Set the desired fixed level value in
3.4.1.2. Level Value
.
2. Set
3.4.1.3. Ramp
to Disabled.
3. Enable
3.4.3. Pump Activations
if desired (see
Pump relay behaviour during
simulation
on page 121).
4. Set
3.4.1.1. Level Simulation Enable
to Enabled to start level simulation.
Set
3.4.1.1. Level Simulation Enable
to Disabled when you wish to stop level simulation.
Note: As fail-safe will not be reported during simulation, a bench simulation of the
LUT400 can be run without a transducer connected.
Note: Simulation Enabled
status will display on LCD even if other faults are present.