Siemens LR 460 User Manual
7ML19985JM01
SITRANS LR 460 (PROFIBUS PA) – INSTRUCTION MANUAL
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Appendix J: PROFIBUS PA Profile
Structure
Structure
PROFIBUS Level Device Design
The device follows the profile block model and is implemented as a Profile 3.01, Class B,
PA device. Standard profile parameters are used to program the Level Transducer Block.
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.
They can be parameterized by acyclic data transfer via PDM.
The device is implemented with one Level Transducer Block (LTB), and two Analog Input
Function Blocks (AIFB1 and AIFB2).
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.
is an input.
Level Transducer Block (LTB)
The Level Transducer Block (LTB) carries out adjustments to the sensor, such as level
calibration. It supplies the outputs utilized by either or both of the AIFBs.
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
TB, and apply any required quality checks, scaling, and Fail-safe operation selections.
TB, and apply any required quality checks, scaling, and Fail-safe 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.
associated status information to PROFIBUS PA, via cyclic data transfer.
sensor
sensor
Level
Transducer
Block
electronics
temperature
Analog Input
Function Block2
Analog Input
Function Block1
PRO
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