Emerson PACSystems RSTi-EP User Manual page 210

User Manual
GFK-2958J
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To restart counting, the internal gate must be reopened. Depending on the parameters set,
counting continues from the current counting value (Interrupt counting) or it starts again
from the load value (Cancel counting).
One-time Counting/ Primary Direction Up
Figure 114: 1-time Counting, Primary Direction Up
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Counting Range
Limits
End value
Lower count limit
Detailed Description of I/O Modules
Upon exceeding the upper or lower count limit, the counter jumps to the other
count limit respectively. The internal gate is automatically closed, the status bit
Overflow performed, or Underflow performed is set and a process alarm will be
triggered if it is parameterized.
Up-counting starts at the load value.
If the parameterized end value -1 is reached during counting in the positive
direction, the counter jumps back to the load value at the next positive count pulse.
The internal gate is automatically closed, the status bit End value reached is set and
a process alarm will be triggered if it is parameterized.
To restart counting, the internal gate must be reopened. Counting starts again at
the load value.
Upon reaching the lower count limit the counter jumps to the upper count limit to
continue counting from there. The status bit Underflow performed is set and a
process alarm will be triggered if it is parameterized. All status bits remain set until
they are reset with the bit Reset status bits in the control word. After a cancelled gate
control, the counting process starts with the load value
Valid range of values
–2 147 483 647 (–2
+2 147 483 648 (2
31 + 1) to +2 147 483 647 (2
31 )
Chapter 5
Oct 2019
31 –1)
195