Instruction Manual
Instruction Manual
D103434X012
Blocks
November 2014
120
Analog Output (AO) Function Block
D Read/Write Capability: RO ‐ Read Only, RW ‐ Read Write
D Mode: The block mode(s) required to write to the parameter
D Double indentations and shaded Index Numbers indicate sub‐parameters
Table B‐27. Analog Output Function Block Parameter Definitions
Label
PARAMETER_NAME
Index
Number
RO /
RW
Block
Mode
Range Initial Value Description
Static Revision
ST_REV
1 RO NA 0 to 65535 0
Data Type: Unsigned16
The revision level of the static data associated with
the function block. The revision value will be
incremented each time a static parameter value in
the block is changed.
Tag Description
TAG_DESC
2 RW ALL 7 bit ASCII Spaces
Data Type: Octet String
The user description of the intended application of
the block.
Strategy
STRATEGY
3 RW ALL 0 to 65535 0
Data Type: Unsigned16
The strategy field can be used to identify grouping
of blocks. This data is not checked or processed by
the block.
Alert Key
ALERT_KEY
4 RW ALL 1 to 255 0
Data Type: Unsigned8
The identification number of the plant unit. This
information may be used in the host for sorting
alarms, etc.
Block Mode
MODE_BLK
5
Data Type: DS‐69
Valid Bits: 7: OOS, 6: IMAN, 5: LO, 4: MAN, 3: AUTO,
2: CAS, 1: RCAS
The actual, target, permitted, and normal modes of
the block.
Target: The requested block mode
Actual: The current mode of the block
(Note: Bit 6 (IMAN) is valid for ACTUAL only)
Permitted: Allowed modes for Target
Normal: Most common mode for Target
TARGET
5.1 RW ALL
OOS
MAN
AUTO
AUTO‐CAS
AUTO‐RCAS
OOS until
block is
configured,
then last valid
target
ACTUAL
5.2 RO ALL OOS
PERMITTED
5.3 RW ALL
OOS+MAN+AUTO+
CAS+RCAS
OOS+MAN+A
UTO+
CAS+RCAS
NORMAL
5.4 RW ALL AUTO
Block Error
BLOCK_ERR
6 RO NA
1: Block Configuration
Error
3: Simulate Active
4: Local Override
5: Device Fault State Set
8: Output Failure
14: Power‐up
15: Out‐of‐Service
Dynamic
Data Type: Bit String (2 byte)
0=inactive
1=active
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. See table B‐26.
Process Variable
PV
7 RO NA
PV Status set equal to
READBACK status
Dynamic
Data Type: DS‐65
The process variable used in block execution. This
value is converted from READBACK to show the
compensation value in the same units as the
setpoint value.
Set Point
SP
8
OOS
MAN
AUTO
PV_SCALE +/‐ 10% Dynamic
Data Type: DS‐65
The SP of the analog block. Can be derived from
CAS_IN, RCAS_IN in normal modes, or can track PV
in MAN, IMan or LO modes. IO_OPTS is used to
determine value of SP in MAN, IMan or LO. If no
IO_OPTS for SP tracking are set, SP will freeze when
mode changes from CAS or RCAS.
Output
OUT
9
MAN
OOS
OUT_SCALE +/‐ 10% Dynamic
Data Type: DS‐65
The primary value and status calculated by the
block in Auto mode. OUT may be set manually in
Man mode.
-Continued-