i4connected Knowledgebase 5.6

Event - The actual event that will be triggered when the current condition is satisfied. Clicking on the Event button will open the Events panel, which allows the user to select an existing event or add a new one.

Parameters - Input signals that can be used in the formula to calculate the expected values. A new parameter can be added by clicking the Add parameter button which opens the Signal List panel. In this view, all the Signals assigned to the current Device are listed. The user can select a signal to act as input for the formula. The parameters can be either a standard signal or a virtual signal. Multiple parameters of mixed types (standard signals and virtual signals) are supported.

Once a parameter is defined, it will be displayed in the table below the Add parameter button. Here the user is able to set the name of the parameter (which will be used inside the formula) and input a test value, allowing the user to test the alarm condition formula.

The Parameters area

Formula - The expression that defines the alarm condition. The expression can use input parameters defined in the Parameters options. The expression can be a simple online calculation or can be a complex, multi-line C# function enclosed in curly brackets {}, in which case a return function is required. The advantage of using complex C# expressions is the availability of variables, loops, etc.

The value returned by the expression must always be boolean! The alarm condition is satisfied only when the formula's result is True.

Simple expression example:

in1 > 10

Multi-line expression example:

var calculatedValue = in1 + 10;
if (calculatedValue > 20) {
    return true;
} else {
    return false;
}

When using parameters in your expression, you are not limited only to the value of that parameter. Several properties of the signal used as input parameters can also be used inside the expression:

For example:

var signalDelta = in1.Delta;
if (signalDelta > 20) {
    return true;
} else {
    return false;
}

The below list illustrates the logical operators that can be used when writing event script list expressions:

The value returned by the expression must always be boolean! The alarm condition is satisfied only when the formula's result is True.

The formula can be tested using the Calculate test result button. This will use the parameter's test value as input value and the result will be listed below.

The Formula area

Computation Mode - The method of using the parameter values.