Communication Partner; System Integration - Endress+Hauser iTEMP PA TMT184 Bedienungsanleitung

TMT184
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Endress+Hauser
Normally the following is valid:
• Max 9 temperature head transmitters in EEx ia applications and
• Max 32 temperature head transmitters in non-hazardous areas
can be connected per bus segment.
Note!
During project planning please note the current consumption of the temperature head transmitter
is 10 ± 1 mA.
5.2.2

Communication partner

In a control system the head transmitter always operates as a slave and, dependent on the applica-
tion, can exchange data with one or more masters. The master can be a PLC, a DCS or a PC fitted
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with a PROFIBUS-DP communication board.
Function blocks
For the description of the function blocks of a unit and definition of unified data access PROFIBUS
uses predefined function blocks ( → chap. 5.2.7 to → chap. 5.2.10). The function blocks imp-
lemented in fieldbus units transmit information regarding the tasks of a unit within the total auto-
mation strategy.
Note!
Detailed information regarding the function blocks can be found in the PROFIBUS-PA
Process Control Devices; Version 3.0 specification.
The following blocks can be implemented in field units according to the Profile 3.0:
• Physical Block:
The physical block contains the unit-specific features of the unit.
• Transducer Block (transmission block):
One or more transducer blocks contain all measurement principle and unit specific parameters of
the unit. The measurement principle (e.g. temperature) according to the PROFIBUS specification
is contained in the transducer blocks.
• Function Block:
One or more function blocks contain the automation function of the unit. One can distinguish
between different function blocks, e.g. analogue input block, analogue output, etc. Each of these
function blocks is used for different applications.
5.2.3

System integration

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On PROFIBUS-PA field units measured values and status are generally transmitted in 5 bytes. One
measurement unit with a number of process variables means that more bytes are transmitted.
In order to bind the field unit into the bus system the PROFIBUS-PA
of the unit parameters such as output data, input data, data format, data quantity and the transmis-
sion speed supported.
This data is contained in a Device Data Base (GSD-File), that is made available to the PROFIBUS-
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PA master during the commissioning of the communications system.
Additionally unit bitmaps, which appear as symbols in the network, can also be included. Using the
profile 3.0 Device Data Base (GSD-File) it is possible to exchange field units from different manuf-
acturers without the need for new planning.
5 Operation
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Profile for
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system requires a description
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