5-20
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PV start
When a PV start is set in the program setting, a PV start is performed in a normal
RUN operation.
The program looks for the first point where PV and the program pattern SP are
equal (both PV and SP include bias) and starts operation from there. PV starts are
of three kinds: rising PV start that looks for a point where PV and SP are equal on
a rising RAMP, falling PV start that looks for a point where PV and SP are equal
on a falling RAMP and bi-directional PV start that looks for such a point both on
rising and falling RAMPs.
Note, however, that if there is no point where PV and SP are equal, operation
starts from the beginning of segment 1.
When a PV start has been implemented, the event operating point and the time
event time are automatically corrected. This is described in the figure shown
below. When PV is at
(1)
in the figure, a rising PV start or a bi-directional PV start
starts from B and a falling PV start starts from C. When PV is at
(2)
in the figure,
a falling PV start or a bi-directional PV start starts from D and a rising PV start
starts from A. When PV is at
(3)
in the figure, any PV start starts from A.
NOTE
PV start is valid for segments in the selected program but not for segments beyond
a pattern link destination.
Chapter 5. FUNCTIONS
A
B
C
D
SP pattern
Current PV value
(1)
(2)
(3)
