Emerson Rosemount 5900C, Справочное руководство

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engineering units and the I/O options attribute (IO_OPTS). In addition, you can limit the SP
value and the rate at which a change in the SP is passed to OUT.
In Cascade mode, the cascade input connection (CAS_IN) is used to update the SP. The
back calculation output (BKCAL_OUT) is wired to the back calculation input (BKCAL_IN) of
the upstream block that provides CAS_IN. This provides bumpless transfer on mode
changes and windup protection in the upstream block. The OUT attribute or an analog
readback value, such as valve position, is shown by the process value (PV) attribute in
engineering units.
To support testing, you can enable simulation, which allows you to manually set the
channel feedback. There is no alarm detection in the AO function block.
To select the manner of processing the SP and the channel output value configure the
setpoint limiting options, the tracking options, and the conversion and status calculations.
C.4 Measurement Transducer block
The Measurement Transducer block contains the actual measurement data, including a
level and distance reading. The transducer block includes information about sensor type,
engineering units, and all parameters needed to configure the transmitter.
Table C-5: Measurement Transducer Block Parameters
Index
Number Parameter Description
1 ST_REV The revision level of the static data associated with the
function block. The revision value increments each
time a static parameter value in the block is changed.
2 TAG_DESC The user description of the intended application of the
block.
3 STRATEGY The strategy field can be used to identify grouping of
blocks. This data is not checked or processed by the
block.
4 ALERT_KEY The identification number of the plant unit. This
information may be used in the host for sorting alarms,
etc.
5 MODE_BLK The actual, target, permitted, and normal modes of the
block. Target: The mode to “go to” Actual: The mode
the “block is currently in” Permitted: Allowed modes
that target may take on Normal: Most common mode
for target
6 BLOCK_ERR This parameter reflects the error status associated with
the hardware or software components associated with
a block. It is a bit string, so that multiple errors may be
shown.
7 UPDATE_EVT This alert is generated by any change to the static data
Reference Manual F
OUNDATION
™
Fieldbus Block Information
00809-0100-5901 September 2019
Rosemount 5900C Radar Level Gauge 303