Fisher FIELDVUEDVC6200f Instruction Manual page 244

DVC6200f Digital Valve Controller
CSEL Function Block
February 2017
The diagram in figure E‐7 shows the internal components of the Control Selector function block:
Figure E‐7. Control Selector Function Block Schematic Diagram
SEL_1
SEL_2
SEL_3
BKCAL_IN MODE
Block Execution
The Control Selector function block picks the high, low, or middle control signal from two or three PID function block
primary outputs and places it at the Control Selector block's primary output. Three back calculation outputs are sent to
upstream PID function blocks.
At the beginning of each scan period, the block calculates the actual mode according to the input status, target mode,
and configured parameter settings. The block steps into the calculated actual mode or stays in the original mode.
Next, the block calculates the forward path primary output:
D In Initializing Manual (IMan) mode, the primary output is unchanged. The BKCAL_SEL_1, BKCAL_SEL_2, and
BKCAL_SEL_3 parameter values are passed to the upstream function blocks.
D In Manual (Man) mode, OUT can be set manually.
D In Automatic (Auto) mode, the block selects SEL_1, SEL_2, or SEL_3 as the primary output based on the selection
type parameter (SEL_TYPE). The output value is sent back to all the upstream blocks.
Note
In Auto mode, when any of the connected SEL_ 1, SEL_2 or SEL_3 inputs have Bad status during block execution, the block
transitions its actual mode to Man. When the Bad SEL_1, SEL_2 or SEL_3 input transitions back to Good status, the block resumes
Auto operation.
All the output parameter status values are set to indicate the status of the block and the status of the corresponding
parameter.
244
OUT_HI_LIM
SEL_TYPE
OUT_LO_LIM
Output
Signal
Limiting
Sort
BCKAL_OUT
Status
OUT
BKCAL_SEL_1
BKCAL_SEL_2
BKCAL_SEL_3
Instruction Manual
D103412X012