Siemens SIMATIC ET 200AL, System Manual

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Counting
4.2 Configuration method 4xCount
Digital input/Digital output module DIQ 16x24VDC/0.5A 8xM12 (6ES7143-5AH00-0BA0)
Equipment Manual, 08/2021, A5E38688112-AD
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Parameter counting function
Input delay DI
This parameter can be used to suppress signal faults. Changes to the signal are only detected
if they are constantly pending longer than the set input delay time.
Note
Influences the counting frequency
When setting the input delay take into account that the counting frequency possible is
automatically reduced at higher values.
In order to achieve the maximum counting frequency of 2 kHz select an input delay smaller
than 0.4 ms.
Counting direction
Use this parameter to select the direction in which counting is carried out:
•
Forward
• Backward.
Edge selection
Use this parameter to select the edge that is counted:
•
At rising edge:
The respective counter counts all the rising edges at the counter input.
• At falling edge:
The respective counter counts all the falling edges at the counter input.
Behavior when a counting limit is exceeded
With this parameter you select the behavior when the high counting limit is violated in the
upward direction or the low counting limit is violated in the downward direction:
•
Stop counting:
After a counting limit is violated, the internal gate is closed. This stops the counting
process. The counter value is set to the opposite counting limit. To start the counting
process again, you must close and reopen the SW gate.
• Continue counting:
After a counting limit is violated, the counter value is set to the opposite counting limit
and counting continues.
Comparison value
With this parameter you specify the comparison value.
The following applies:
•
Low counting limit ≤ Comparison value ≤ High counting limit
Start value
With this parameter you specify the start value.
The following applies:
•
Low counting limit ≤ Start value ≤ High counting limit