Rockwell Automation AADvance Controller Safety Manual - Manual (Page 77)

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Document: 553630
ICSTT-RM446K-EN-P Issue: 10
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4-21
HART
The AADvance controller supports HART communications using dedicated
HART modems on each analogue input and output channels allowing HART
field device status, diagnostic data and process signal data to be integrated into
the application logic, increasing the level SIF diagnostics significantly. The
AADvance Analogue Input/Output modules use HART commands #03 to
collect data from the field device as defined by Revision 5 of the HART
specification.
The extra data available from HART enabled field devices is reported to the
application in custom data structures.
The T9K_AI_HART and T9K_AI_HART_FULL structures provide the
following information:
 Current in milli-amps
 process measurement in engineering units
 errors on HART communication seen by device
 status of the field device
 time in milli-seconds since the last update.
Typical uses of this data are:
 To compare the measured process value from the Analogue input channel
with the process variable value transmitted over HART from the field
device to detect discrepancies.
 To monitor the field device status and report device status and report
diagnostic errors or manual configuration changes
Note: The update rate for HART data from field devices is significantly slower
than the update rate for the 4-20mA Analogue signal itself, HART data may
take up to 4 seconds to update, depending on the device type and
configuration.