Rockwell Automation AADvance Controller Demo Unit User Manual
Page 88
Demo Unit User Manual (AADvance Controller)
5-22
Document: 553850 Issue 1.2: March 2011
<tagname>.DEVICE BYTE
Device status (†)
Bit 7: field device malfunction
Bit 6: configuration changed
Bit 5: cold start
Bit 4: more status available
Bit 3: analogue output current fixed
Bit 2: analogue output saturated
Bit 1: non-primary variable out of
limits
Bit 0: primary variable out of limits
Note: (†) The device status byte mimics the HART field device status. Appendix E of
the HART Application Guide gives details.
About Threshold Values for Analogue Inputs
The module determines the channel state and the line fault status by comparing the
channel input current with defined threshold values. You can define your own
threshold values or use a set of default values. The values you choose for the module
are inherited by each channel; you can define different thresholds for individual
channels later.
Thresholds are specified in counts, with 0 (zero) being 0mA, 1,024 being 4mA, and
5,120 being 20mA.
Note: When the system is operational you should change these values only using an
on-line update.
The AADvance controller provides hysteresis on the thresholds for increasing and
decreasing values to prevent chatter. The Workbench updates the reporting values
during every application cycle.