User's Manual
Table Of Contents
- 8 Parameter reference
- 9 Service and maintenance
- 10 Diagnosing and troubleshooting
- 11 Technical data
- 12 Dimension drawings
- 12.1 Threaded horn antenna
- 12.2 Threaded horn antenna with extension
- 12.3 Flanged horn antenna
- 12.4 Flanged horn antenna with extension
- 12.5 Flanged encapsulated antenna (2"/DN50/50A sizes only)
- 12.6 Flanged encapsulated antenna (3"/DN80/80A sizes and larger)
- 12.7 Threaded PVDF antenna
- 12.8 Threaded connection markings
- 12.9 Raised-Face flange per EN 1092-1 for flanged horn antenna
- 12.10 Raised-Face flange per EN 1092-1 for flanged encapsulated antenna
- 12.11 Flat-Face flange
- 12.12 Process connection tag (pressure rated versions)
- A Appendix A: Technical reference
- B Appendix B: PROFIBUS PA profile structure
- C Appendix C: Communications via PROFIBUS
- D Appendix D: Certificates and Support
- 13 List of abbreviations
- 14 LCD menu structure
- Glossary
- Index
SITRANS LR250 (PROFIBUS PA)
Operating Instructions, 01/2014, A5E32221386-AB
221
Appendix B: PROFIBUS PA profile structure
B
B.1
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.
B.2
Block Model
The Block Model represents how measured values are recorded and processed. All data is
viewed from the perspective of the DCS or PLC, so information from the sensor is an input.
The functions of the device are divided into blocks with different areas of responsibility. The
blocks are configured by parameters.
The device is implemented with one Physical Block, one Transducer Block (TB), and two Analog
Input Function Blocks (AIFB1 and AIFB2).
Physical Block
The Physical Block handles functionality and descriptions relating to the device as a whole: for
example, LCD Contrast (functionality) and Firmware Revision and Tag (descriptions).
Transducer Block (TB)
The Transducer Block carries out adjustments to the sensor, such as level calibration and
volume calibration. It supplies the measurement value [Primary Value (PV), Secondary Value 1
(SV1), or Secondary Value 2 (SV2)] utilized by either or both of the AIFBs.