Rockwell Automation 1794-OF8IH FLEX Isolated Input/Output HART Analog Modules - Manual (Page 60)

Publication 1794-UM065B-EN-E - September 2010
48 1794-IF8IH and 1794-OF8IH Configuration
Formats 8…15, with pre-programmed fault levels, see Data Formats and
Error Ranges on page 42.
The Low Alarm is active for Data Formats 0…7, unless disabled by a "0"
(default) value of Low Alarm Limit. The Low Alarm is not available for Data
Formats 8…11, since the normal input range includes 0 mA. The Low Alarm
is always active for Data Formats 12…15, with pre-programmed fault levels,
see Data Formats and Error Ranges on page 42.
These alarm types are meant to accommodate traditional direct measurement
loops and loops incorporating remote transmitters.
See to Data Format (8 of 4 bits) on page 39 and 1794-IF8IH Data Formats on
page 40 for specific explanations of Data Formats, and Remote Low Low
Alarm Limit (8 of 16 bit) on page 41, Remote High High Alarm Limit (8 of 16
bit) on page 42, Low Alarm Limit (8 of 16 bit) on page 42, High Alarm Limit
(8 of 16 Bit) on page 43 and Data Formats and Error Ranges on page 42 for
specific explanations of Error Ranges.
High Alarm (8 of 1 bit each)
Alarm signal for input overrange.
For Data Formats 0…7, alarm thresholds are adjustable by the High Alarm
Limit parameter. This signal is active, unless disabled by a "0" (default) value of
High Alarm Limit.
For Data Formats 8…15, alarm thresholds are preset. This signal is always
active.
Range: 0=normal, 1=input overrange
Data Table Reference: high alarm, Status Word 0, bits 8…15
Low Alarm (8 of 1 bit each)
Alarm signal for input underrange.
For Data Formats 0…7, alarm thresholds are adjustable by the Low Alarm
Limit parameter. This signal is active, unless disabled by a "0" (default) value of
Low Alarm Limit.
Data Formats 8…11 do not issue Low Alarm due to input low conditions,
since the normal input range includes 0 mA.
For Data Formats 12…15, alarm thresholds are preset. This signal is always
active.
Range: 0=normal, 1=input underrange
Data Table Reference: Low Alarm, Status Word 0, bits 0…7