Introducing HART
Multiplexer Data Flow
The Path from HART Field Instrument to Analog I/O
The HART multiplexer is a passive, pass-through device placed between analog
HART field instruments and analog I/O modules.
The physical location of the I/O does not matter. The I/O can be an STB I/O module that resides in the STB HART multiplexer island. Or it can be a module that resides in a Quantum, Premium, M340, or third-party platform rack.
NOTE: In the following data flow diagram, the Ethernet transmission is performed via Modbus TCP. The PC with asset management software is equipped with serialto-Ethernet connector software.
The following figure outlines the flow of data for non-HART tolerant I/O:
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Introducing HART
I/O Placement
For both HART tolerant I/O and non-HART tolerant I/O, the physical location of the
I/O can vary. The I/O can be an STB analog I/O module that resides in the STB
HART multiplexer island. Or it can be an analog I/O module that resides in a separate rack. Typical I/O placement locations include the following:
Placement of I/O modules Platforms
The STB HART multiplexer island STB
A separate I/O drop z z z z z
STB
M340
Premium
Quantum
Third party platforms
Use this design for...
New STB networks
Existing networks
You can create a topology that combines both designs and places analog I/O modules both in the multiplexer island and in a separate I/O drop.
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HART
Planning the HART Multiplexer
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Planning the HART Multiplexer
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Introducing the STB HART Multiplexer
The HART multiplexer is a specific-purpose STB island. An STB HART multiplexer island is a modular distributed I/O system. This chapter describes how to plan the installation of an STB HART multiplexer island.
What Is in This Chapter?
This chapter contains the following topics:
Topic
Island Segments
Extending the Island Bus
Enclosing the HART Multiplexer
The Power Distribution Modules
Logic, Sensor, and Actuator Power Distribution on the Island Bus
Understanding Multiplexer Island Power Supply and Consumption
Selecting Power Supplies
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