Emerson Rosemount 5900C, Reference Manual

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Table C-4: Analog Output Function Block System Parameters
(continued)
Parameter Units Description
BLOCK_ERR None The summary of active error conditions associated with the
block. The block errors for the AnalogOutput block are
Simulate Active, Input Failure/Process Variable has Bad
Status,Output Failure, Read back Failed, and Out of Service..
CAS_IN EU of PV_SCALE The remote setpoint value from another function block.
IO_OPTS None Allows you to select how the I/O signals are processed. The
supported I/O options for the AO function block are SP_PV
Track in Man, Increase to Close, and Use PV for BKCAL_OUT.
CHANNEL None Defines the output that drives the field device.
See
Analog Output block .
MODE None Enumerated attribute used to request and show the source of
the setpoint and/or output used by the block.
OUT EU of XD_SCALE The primary value and status calculated by the block in Auto
mode. OUT may be set manually in Man mode.
PV EU of PV_SCALE The process variable used in block execution. This value is
converted from READBACK to show the actuator position in
the same units as the setpoint value.
PV_SCALE None The high and low scale values, the engineering units code, and
the number of digits to the right of the decimal point
associated with the PV.
READBACK EU of XD_SCALE The measured or implied actuator position associated with
the OUT value.
SIMULATE EU of XD_SCALE Enables simulation and allows you to enter an input value and
status.
SP EU of PV_SCALE The target block output value (setpoint).
SP_HI_LIM EU of PV_SCALE The highest setpoint value allowed.
SP_LO_LIM EU of PV_SCALE The lowest setpoint value allowed.
SP_RATE_DN EU of PV_SCALE
per second Ramp rate for downward setpoint changes. When the ramp
rate is set to zero, the setpoint is used immediately.
SP_RATE_UP EU of PV_SCALE
per second Ramp rate for upward setpoint changes. When the ramp rate
is set to zero, the setpoint is used immediately.
SP_WRK EU of PV_SCALE The working setpoint of the block. It is the result of setpoint
rate-of-change limiting. The value is converted to percent to
obtain the block’s OUT value.
C.3.1 Setting the output
To set the output for the AO block, you must first set the mode to define the manner in
which the block determines its setpoint. In Manual mode the value of the output attribute
(OUT) must be set manually by the user, and is independent of the setpoint. In Automatic
mode, OUT is set automatically based on the value specified by the setpoint (SP) in
F
OUNDATION
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Fieldbus Block Information Reference Manual
September 2019 00809-0100-5901
302 Reference Manual