Siemens SITRANS T3K PA, Instruction Manual

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Instruction Manual 7NG3213
64
SITRANS T3K PA
C79000-B7174-C55-04
1.3 PROFIBUS connection
The PROFIBUS (Process Field Bus) is an open communication system for
automation technology. A detailed description of its properties can be found in
chapter 7, page 108. The most important information for operation is listed below:
1.3.1 Setting the PROFIBUS address
The PROFIBUS address is set to 126 as standard. It can be set to another value
by the parameter setting tool, e.g. SIMATIC PDM. The set PROFIBUS address
may only be assigned once on the same bus system.
1.3.2 Useful data about PROFIBUS
Floating point representation of the measured value
Bits 7 6 5 4 3 2 1 0
Bytes VZ E
1 2
7
2
6
2
5
2
4
2
3
2
2
2
1
E M
2 2
0
2
--1
2
--2
2
--3
2
--4
2
--5
2
--6
2
--7
M
3 2
--8
2
--9
2
--10
2
--10
2
--12
2
--13
2
--14
2
--15
M
4 2
--16
2
--17
2
--18
2
--19
2
--20
2
--21
2
--22
2
--23
VZ: sign; 0 = positive, 1 = negative
M: Mantissa
E: Exponential
The useful data are continuously updated by the cyclic service of PROFIBUS.
This is the measured value in SITRANS T3K PA. It can be a temperature,
resistance or voltage value depending on the configuration. The measured value
is divided into a floating point value (4 bytes) and the appropriate quality indicator
(1 byte).