Siemens SIMATIC ET 200AL, Системное руководство

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Alarms
6.5 Example program for program alarms
Diagnostics
84
Function Manual, 11/2019, A5E03735838-AF
6.5.2 Example 1: Program alarm without associated values
Introduction
In this example, you create a program alarm for the maximum and the minimum fill level.
How the example works
When the maximum fill level is exceeded in the tank, a program alarm with the alarm text for
the excessive fill level is output.
When the minimum fill level is undershot in the tank, a program alarm with the alarm text
indicating that the fill level is too low is output.
Steps
The following steps are necessary for this example:
1.
Define tags for signal acquisition
2. Create function block
3. Create program alarms
4. Call function block
5. Edit alarm text
Define tags for signal acquisition
The following table shows the tags that are used in this example. Define these tags in the
standard tag table. The standard tag table is available in the project tree under "PLC tags".
Table 6- 1 Tags for fill level alarms
Name Data type Description
max BOOL Tag for maximum fill level
If "max" = 1, the maximum fill level is exceeded.
min BOOL Tag for minimum fill level
If "min" = 1, the minimum fill level is undershot.
The figure below shows the standard tag table with the defined tags "max" and "min".
Figure 6-6 Define tags