Siemens SITRANS SL - Cyclic Data Transmission over PROFIBUS; Cyclic Data Structure

Interfaces to automation systems
8.1 PROFIBUS DP interface
SITRANS SL
132 Operating Instructions, 12/2010, A5E01132948-04
8.1.4 Cyclic data transmission over PROFIBUS
8.1.4.1 Cyclic data structure
Specific parameters physical block for passive bus tap-off
The following user data can be exchanged cyclically using the PROFIBUS.
Parameter name Meaning Direction seen
from gas analyzer
Data type Length in byte
Concentration Measured value
and status.
Output DS-33 5
Transmission Measured value
and status.
Output DS-33 5
Pressure Process pressure
in mbar.
Input DS-33 5
Temperature Process
temperature in
Celsius Degree.
Input DS-33 5
DS 33 data type
Each value is represented as a 5 bytes value. The first four bytes build the measurement
value, transmitted according to IEEE-754. The fifth byte is used for status.
Byte 1 Byte 2 Byte 3 Byte 4 Byte 5
Value in IEEE-754 floating point Status
Exponent Fraction -
MSB - -