Profibus Pa Profile Structure; Profibus Level Device Design; Block Model For Recording And Processing Measured Values - Siemens Sitrans LR 460 Instruction Manual

PROFIBUS PA Profile Structure

PROFIBUS Level Device Design

The device follows the profile block model and is implemented as a Profile 3.0, Class B,
PA device. Standard profile parameters are used to program the level transducer block.

Block Model for recording and processing measured values

The functions of the device are divided into blocks for different areas of responsibility.
They can be parameterized by acyclic data transfer via PDM.
sensor
The device is implemented with one Physical Block (PB1), one Level Transducer Block
(LTB1), and two Analog Input Function Blocks (AIFB1 and AIFB2).
All data is viewed from the perspective of the DCS or PLC, so information from the sensor
is an input.
Transducer Block (TB)
The Level Transducer Block (LTB) carries out adjustments to the sensor, such as level
calibration and volume calibration. It supplies the outputs utilized by either or both of the
AIFBs.
Analog Input Function Blocks AIFB1 and AIFB2
The two AIFBs are completely independent of each other. They utilize the output from the
Level TB, and apply any required quality checks, scaling, and Failsafe operation
selections.
The output of an Analog Input Function Block supplies the measured value and
associated status information to PROFIBUS PA, via cyclic data transfer.
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sensor
electronics
temperature
Transducer Block
SITRANS LR 460 – INSTRUCTION MANUAL
Analog Input
Function Block1
Analog Input
Function Block2
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