Endress+Hauser Prosonic S FMU95, Руководство по эксплуатации

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Prosonic S FMU95 Commissioning
E Hauser 69
6.4 Parametrization of the cyclic data telegram
!
Note!
• Basic information on the cyclic data exchange between the measuring instrument and an
automation system (e.g. PLC) are given in the manual BA00034S "PROFIBUS DP/PA -
Guidelines for planning and commissioning"
• The cyclic data exchange requires that the correct device type files (GSD) have been loaded to the
automation system. For details

ä
46 "Loading the device database and type files (GSD)".
6.4.1 Data format
With PROFIBUS DP, analogue measuring values are transmittted to the PLC in blocks (modules) of
5 bytes each. The measured value is encoded in the first four bytes in the form of a floating point
number accordint to the IEEE standard. The fifth byte containes a standardized status information
about the instrument. For details refer to the manual BA00034S, "PROFIBUS DP/PA - Guidelines
on planning and commissioning".
6.4.2 Modules for the cyclic data telegram
Each AI Block of the Prosonic S FMU95 provides a module of five bytes for the cyclic data telegram.
According to the PROFIBUS specifications "Profiles for process control devices" there are two
options for each module:
•
AI (OUT) : The module is contained in the cyclic data telegram.
• Free Place : The module is not contained in the cyclic data telegram.
The options are selected in the configuration tool of the respective PLC. For details refer to the
manual of the tool.
6.4.3 Default configuration of the cyclic data telegram
5-channel version (FMU95 - *****A***)
AI Blocks 1 to 5 are contained in the data telegram and transmit one level value each. The other AI
Blocks (AI6 to AI20) are not used by default. If required, they can be used to transmit sensor
temperatures, averages or sums.
Byte Block Access type Format Measured value
1)
1) The allocation of the measured values can be changed in "output calculations/analog input/analog input N/
measured value N" (N = 1 to 20).
Unit
2)
2) The unit can be changed in
"level/level N/basic setup/unit level"
"device properties/operating params/distance unit"
"device properties/operating params/temperature unit"
0, 1, 2, 3 AI 1 read IEEE754 level 1 m
4 Status byte Status level1 -
5, 6, 7, 8 AI 2 read IEEE754 level 2 m
9 Status byte Status level2 -
10, 11, 12, 13 AI 3 read IEEE754 level 3 m
14 Status byte Status level3 -
15, 16, 17, 18 AI 4 read IEEE754 level 4 m
19 Status byte Status level4 -
20, 21, 22, 23 AI 5 read IEEE754 level 5 m
24 Status byte Status level5 -