Analog Input Function Blocks 1 And 2; Output Conversion - Siemens SITRANS L Operating Instructions Manual

3. Linearization can be carried out to accommodate complex vessel shapes, or to provide level
to volume conversion.
4. The Transducer Block provides three possible outputs:
– Primary Value (PV) / Level (level units)
– Secondary Value 1 (SV1) / Level (level units)
– Secondary Value 2 (SV2) / Distance (sensor units)
Referenced from Sensor reference point
1)
Sensor offset (2.3.7.3.) (Page 96) is a constant offset (negative or positive) that can be
2)
added to sensor value to compensate if the sensor has been changed.
Level Offset (default O) can compensate for specific vessel configurations.
3)
Electronics temperature
The Transducer Block monitors the internal temperature of the device electronics. A change
in temperature can provide advance warning of a possible device failure, and allow for
preventive maintenance.
If a temperature limit is exceeded, the output value is unchanged but the output status
changes. (The permitted limits correspond to those of the permitted ambient temperature.)
Peak indicators allow you to check the maximum and minimum temperatures that have
occurred. To see peak temperature values, Open the menu View – Device Diagnostics,
select Device Status, and click on the tab Device Status.
D.5

Analog Input Function Blocks 1 and 2

The input to the AIFB is a value with a status. See Transducer Block function groups
(Page 195) for a graphic representation.
D.6

Output conversion

The Analog Input Function Blocks can modify the output value.
Scaling
Output scaling (2.6.6.) (Page 112) allows you to scale the output to any desired units.
Fail-safe
If the status of the input (TB output value or Simulation Value) is bad, the fault logic can
output either the last usable measured value, or a given substitute value. Set Mode (2.6.9.1.)
(Page 115) and, if desired, define a value in Value (2.6.9.2.) (Page 115).
SITRANS LR200 with PROFIBUS PA
Operating Instructions, 07/2021, A5E32337680-AF
PROFIBUS PA profile structure
D.5 Analog Input Function Blocks 1 and 2
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