An instance of this function block type models the operation of a
dual set of sensors which can sense both the presence of a workpiece
at a position POS between the two positions
P0
and
P1
inclusive, and whether the type of the workpiece given by the
STYLE
input matches the reference style
REFSTYLE
(an instance of the VSTYLE
data
type) when the workpiece is present. It is typically used to position
a sensor pair at a specified location along a conveyor modelled by an
instance of the CNV_MDL
type
or its enclosing CNV_MDLL
or
CNVG_MDLL
types, for
instance as in the sortation/inspection
testbed.
As modeled by the Execution Control Chart (ECC) and Algorithm shown
below, the operation of the block is triggered by an event at the
SENSE
input and results in an event at the
IND
output when the value of either or both of the
PRESENT
and
MATCH
sensors changes.