Emerson FIELDVUE DVC6200f, Instruction Manual

Page: 193 / 326

DO Function Block
November 2010 181
SP tracks PV in LO, SP Track retained target in Man
or LO, Fault State to Value, Use Fault State value on
restart, Target to Man if Fault State activated, and US
PV for BKCAL_OUT.
Note
You can configure the supported I/O
options in Out of Service mode only.
The SP_PV Track in Man option permits the set point
to track the process variable when the block is in
Manual mode. With this option enabled, the set point
(SP_D [8]) becomes a copy of the process variable
(PV_D [7]), and a manually-entered SP_D [8] value is
overwritten on the block’s next execution cycle. This
option can prevent a state change when transitioning
from Manual to Automatic mode. You can disable this
option in Manual or Out of Service mode only.
The Invert option inverts the set point at SP_D [8]
before it is stored in OUT_D [9]. With this option
enabled, OUT_D [9] becomes an inverted copy of
SP_D [8] where non-zero values of SP_D [8] are
considered a logic 1. With this option disabled, OUT_D
[9] is a direct copy of SP_D [8]. The readback value is
processed through the Invert option to become PV_D
[7]. The Use PV for BKCAL_OUT option specifies that
BKCAL _OUT equal the value of the process variable
(PV_D [7]) instead of the set point (SP_D [8]). If you
do not enable this option, BKCAL_OUT will equal
SP_D [8].
Output Block PV Status
The Output Block PV Status is determined by the
value of the PlantWeb Alerts Set PV Status parameter
in the transducer block (PWA_SET_STATUS [97]),
the Transducer Block mode, and enabled Active
PlantWeb alarms. Refer to table 4-11.
Block Errors
Table 4-71 lists conditions reported in the
BLOCK_ERR [6] parameter. Conditions in italics are
not applicable for the DO block and are provided only
for your reference.
Table 4-71. BLOCK_ERR Conditions
Condition
Number
Condition Name and Description
0 Other (N/A)
1
Block Configuration Error - SHED_OPT or CHANNEL set to
0 (uninitialized)
2 Link Configuration Error (N/A)
3
Simulate active - Simulation is enabled and the block is using
a simulated value in its execution.
4 Local Override - Device in fault state. Actual mode LO.
5
Device Fault State Set - DO block in fault state after
FSTATE_TIME because of Bad status or IFS substatus on
CAS_IN_D or Resource block commanded fault state.
6
Device Needs Maintenance Soon - Indicates a Maintenance
PlantWeb Alert condition is active if Block Error Reporting is
enabled. See page 70.
7
Input failure/process variable has Bad status - PV has bad
status and Feature Select in the Resource block has the Out
Readback bit set or the transducer block mode is Out of
Service.
8
Output failure - PV has bad status or the transducer block
mode is Out of Service.
9 Memory Failure (N/A)
10 Lost Static Data (N/A)
11 Lost NV Data (N/A)
12 Readback Check Failed (N/A)
13
Device Needs Maintenance Now - Indicates Failed
PlantWeb Alert condition is active if Block Error Reporting is
enabled. See page 70.
14
Power Up - This condition exists after power up until actual
mode is not Out of Service.
15 Out of Service - The block is in Out of Service (OOS) mode.
Action on Fault Detection
Fault State is caused by one of three sources: A
status pertaining to CAS, A status pertaining to RCAS,
or SET_FSTATE [29] in the resource block. To
implement Fault State, configure the following
parameters:
IO_OPTS [14]: Determines the action OUT_D [9] will
take upon a fault state. If the IO_OPTS [14] “Fault
State to Value” is not selected, then OUT_D [9] holds
its last position when Fault State is set. If “Fault State
to Value” is selected, OUT_D [9] goes to the
FSTATE_VAL_D [20] value when Fault State is set.
FSTATE_TIME [19]: The length of time, in seconds,
that the DO block will wait to set Fault State. When
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