How to
Automatically Configuring the Y Axis Scale
You configure the trend chart to automatically scale the y axis. The trend chart has two y axis, one to the left and one to the right. You can use this procedure to scale both axis.
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 WebStation, in the System Tree pane, select the trend chart you want to configure.
On the Trend Chart toolbar, click Settings .
In the Auto scale left axis box and the Auto scale right axis box, select True .
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Click OK .
Trend Chart Axes in WebStation
Configuring the X Axis with a Relative Time Span
Configuring the X Axis with an Absolute Time Span
Showing Trend Chart Grid Lines
Manually Configuring the Y Axis Scale
Saving Current Trend Chart Settings
Trend Chart View
Trend Chart Settings Dialog Box – Axis Tab