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Rockwell Automation Publication 1718-UM001A-EN-E - December 2019 35
Appendix
C
Additional HART Protocol Information
This appendix discusses these topics.
This appendix describes the HART protocol and provides references for
additional information about the protocol. Consult the HART protocol
specification and vendor-provided documentation for specifics on
HART commands.
This appendix provides the following:
•
HART protocol background information
•
Common practice command sets
•
Extended command sets
•
References to additional information
HART Field Communication Protocol is widely accepted in the industry as the
standard for digitally enhanced 4…20 mA communication with smart field
instruments. The HART Protocol message structure, command set, and status
are discussed in this appendix.
The HART command set is organized into these groups and provides read and
write access to a wide array of information available in smart field instruments:
•
Universal commands provide access to information that is useful in normal
plant operation such as the instrument manufacturer, model, tag, serial
number, descriptor, range limits, and process variables. All HART devices
must implement universal commands.
•
Common practice commands provide access to functions that can be
carried out by many devices.
•
Device specific commands provide access to functions that can be unique
to a particular device.
Topic Page
Message Structure 36
Response Code and Field Device Status 37
HART PV, SV, TV, and FV Status 43