How to
Editing the Trend Chart Settings
You configure the scale of the trend chart axes, the presentation of series, and the calculation method to make it easier to interpret the series, representing the trend log records, in the trend chart.
The x-axis of the trend chart represents time. The time span of the axis can be set with a fixed start and end time or with an end time relative to the present time. The axis can be quick-scaled to show the last hour, last day, last month, or last year.
Absolute time span and relative time span, schematic
The y-axis refers to the measurement unit that the variable represents. The scale of the y-axis can be set manually or by auto scale. You can configure the trend chart to present series on one y-axis or two y-axes, one to the left and one to the right. Use two y-axes to present series with different ranges in the same trend chart.
One y-axis and two y-axes, schematic
To make reading easier, grid lines can be shown in the trend chart. Grid lines can be shown in both the x- and y-direction, independent of each other.
Grid lines, schematic
In WorkStation, in the System Tree pane, select the trend chart.
On the Trend Chart toolbar, click Open trend chart settings button
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In the Trend Chart Settings dialog box, edit the trend chart settings.
Click OK .
Trend Chart Axes
Trend Chart Settings Dialog Box – Axes Tab
Trend Chart Event Icons
Trend Chart View