Status Handling; Advanced Features - Emerson Rosemount 5900S Series Reference Manual

Reference Manual
00809-0100-5900, Rev CA
June 2014

4.11.10 Status Handling

4.11.11 Advanced
Features
Section 4. Configuration
Normally, the status of the PV reflects the status of the measurement value,
the operating condition of the I/O card, and any active alarm condition. In Auto
mode, OUT reflects the value and status quality of the PV. In Man mode, the
OUT status constant limit is set to indicate that the value is a constant and the
OUT status is Good.
The Uncertain - EU range violation status is always set and the PV status is
set high- or low-limited if the sensor limits for conversion are exceeded.
In the STATUS_OPTS parameter, you can select from the following options to
control the status handling:
BAD if Limited – sets the OUT status quality to Bad when the value is higher
or lower than the sensor limits.
Uncertain if Limited – sets the OUT status quality to Uncertain when the
value is higher or lower than the sensor limits.
Uncertain if in Manual mode – The status of the Output is set to Uncertain
when the mode is set to Manual.
NOTE!
The instrument must be in Manual or Out of Service mode to set the status
option.
The AI block only supports the BAD if Limited option. Unsupported options
are not grayed out; they appear on the screen in the same manner as
supported options.
The AI function block provided with Rosemount fieldbus devices provides
added capability through the addition of the following parameters:
ALARM_TYPE – Allows one or more of the process alarm conditions
detected by the AI function block to be used in setting its OUT_D parameter.
OUT_D – Discrete output of the AI function block based on the detection of
process alarm condition(s). This parameter may be linked to other function
blocks that require a discrete input based on the detected alarm condition.
VAR_SCAN – Time period in seconds over which the variability index
(VAR_INDEX) is computed.
VAR_INDEX – Process variability index measured as the integral of average
absolute error between PV and its mean value over the previous evaluation
period. This index is calculated as a percent of OUT span and is updated at
the end of the time period defined by VAR_SCAN.
Rosemount 5900S Series
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