Axes dialog

Accessing the dialog

To access the Axes dialog for a specific Trend Control screen object, first access the Object Properties dialog for that screen object and then click Axes.

The dialog in detail

Figure 1. Axes dialog
Axes dialog

The Axes dialog contains the following elements:
Area / Element Name Description
X-axis Data Type Date/Time  
Numeric  
Scale Format  
Period (when Data Type is Date/Time) Type
  • Auto: When this option is selected, the Trend Control object works with Start Date/Time when is it triggered to Pause Mode, and it works with Time Before Now when it is triggered to Play Mode.
  • Start Date/Time: When this option is selected, the value of the tag configured in the Time field defines the starting Date/Time for the data displayed on the object.
  • Time Before Now: When this option is selected, the value of the tag configured in the Time field defines the amount of time before the current Date/Time, which will be used as the starting Date/Time for the data displayed on the object.
Duration Defines the Period of data displayed on the object. You can configure a string tag in this field, so you can change the duration dynamically during runtime by changing the value of this tag. The format of the value supported by this property is HH:MM:SS. For example, 36:00:00 (thirty six hours).
Time This field is optional. The value of the tag configured in this field represents a period of time, rather than a specific date or time. The meaning of this value depends on the option set for the Type property.
  • When the Type is set as Start Date/Time, the value of the tag configured in this field must comply with the format Date Time. For example, 02/10/2005 18:30:00.
  • When the Type is set as Time Before Now, the value of the tag configured in this field must comply with one of the following formats:
    1. Time (string value). For example, 48:00:00 (forty eight hours).
    2. Number of hours (real value). For example, 2.5 (two hours and thirty minutes).

If the Time field is left blank (or if the tag configured in this field has the value 0), the object displays data up to the current Date/Time.

Period (when Data Type is Numeric) Min / Max Minimum and maximum values displayed on the X-axis.

The Min and Max properties can hold real numeric values up to six decimal places. If you need more precision than that, then you must configure the Min and Max properties with Real tags and then store the values in those tags.

Eng. Units Engineering Unit (e.g., Kg, BTU, psi) that is associated with the X-axis during runtime.
Grid Divisions You can configure the number of divisions (vertical or horizontal lines) drawn on the object for the X and/or Y-axis respectively, as well as the color of these lines.
Color  
  Time Bar When checked, the Time bar is displayed below the X-axis during runtime; otherwise, it is hidden. The time bar is a standard interface that can be used by the operator to change the X-axis scale during runtime.
Scroll Bar When checked, the Scroll bar is displayed below the X-axis during runtime; otherwise, it is hidden. The time bar is a standard interface that can be used by the operator to navigate through the X-axis scale during runtime. Optionally, you can configure a tag in the Scroll bar field, which defines the period for the scroll bar. If this field is left empty, the period is equal to the current value for Duration of the X-axis.
Cursor The cursor is an optional ruler orthogonal to the X-axis, which can be used during runtime to obtain the value of any pen at a specific point (intersection of the pen with the cursor). When you click this button, the Cursor dialog launches, where you can configure the settings for the optional vertical cursor as follows:
Positon Defines the position of the X-axis, as well as its direction and orientation, as follows:
Y-axis Grid Divisions You can configure the number of divisions (vertical or horizontal lines) drawn on the object for the X and/or Y-axis respectively, as well as the color of these lines.
Color  
Scale Min / Max Default minimum and maximum values displayed in the Y-axis. Used when more than one pen shares the same scale (Multiple Sections disabled), and/or for the points whose Min and Max fields are not configured (left blank).
Multiple Selections When checked, the Y scale is divided automatically into one section for each pen; otherwise, all pens share the same Y scale.
Format Launches a dialog for configuring the format of the labels displayed by the Y-axis.
Note: The tags configured in the Period/Range fields are automatically updated when the user changes the X scale dynamically during runtime, using the Time bar embedded in the object.