Siemens SIMATIC ET 200AL, System Manual

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Counting
4.3 Examples of counting
Digital input/Digital output module DIQ 16x24VDC/0.5A 8xM12 (6ES7143-5AH00-0BA0)
Equipment Manual, 08/2021, A5E38688112-AD
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4.3 Examples of counting
In this section, you will find examples of the behavior of the counter and how you can specify
this behavior. You specify the properties of the counter in the parameter assignment.
The boundary conditions apply for the following examples:
•
You set the bit SW_GATE to "1", the counting process starts.
• If you reset the bit SW_GATE before a count limit is reached, the counting process stops.
Set the bit SW_GATE to restart the counting process.
The value with which the counting process starts again depends on the content of the
control interface.
These conditions only apply if you do not use a HW gate (configuration method 2xCount).
Behavior DQ - Count value between a comparison value and the high counting limit (counting
direction forward)
The following section shows the behavior of the count output with the parameter
assignment "Set output DQ: Count value between a comparison value and the high counting
limit".
The count output is set to "1" if the current values lies between the comparison value and the
high count limit.
You can optionally enable a hardware interrupt through the parameterization. This is
generated with the rising edge of the count output.
The following figure shows an example of the signal state of the count output depending on
the parameterization mentioned above.
Figure 4-13 Behavior DQ and hardware interrupt