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Designing a Sequential Control System based on the Example of a Drill
S7-GRAPH for S7-300/400 Programming Sequential Control Systems
C79000-G7076-C526-01
3-19
3.14
Test Function: Control Sequencer
Control Sequencer is a test function with which you can test the sequencer in
S7-Graph in all modes. All the settings and entries for the dialog box have the
same effect as the corresponding FB parameters.
The entries in the "Control Sequencer" dialog box can be different from the settings
you used to compile the sequencers. The dialog box settings have priority.
"Control Sequencer" Dialog box
The "Control Sequencer" dialog box is used both as an output field that displays
the current settings and as an input field in which you can change the current
status.
If you acknowledge an error, initialize the sequencer or want to change the step to
the manual mode, call the dialog box with the menu command Debug > Control
Sequencer.
Acknowledge
If the "Acknowledge errors" option is clickd, you acknowledge a pending error
message with the "Acknowledge" button. In this way, you can acknowledge a
disturbance caused, for example, by the configured monitoring time in Step 2 being
exceeded.
Note, however, that before you acknowledge the error you must make sure that the
supervision or interlock conditions that led to the error are no longer satisfied.
After an error has occurred, you can enable the next step in the sequencer by
satisfying the step enable condition since the last step enable condition in the cycle
in which you acknowledge has priority over the supervision. You must nevertheless
acknowledge the error.
If the error was caused because the undisturbed activation time Step name.U has
exceeded the configured monitoring time, you can move on the sequencer by
clicking the "Acknowledge" button.
This is possible because the Step name.U variable is set to "0" when you
acknowledge.
Initialize
With the "Initialize" button, you can restart the sequencer completely with the
defined initial step.