How to
Configuring the X Axis with a Relative Time Span
You you configure the trend chart time span of the x axis relative to the series current end point time to automatically adapt the trend chart to display the current time and the latest records within the specific time span.
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.
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.
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.
In WebStation, in the System Tree pane, select the trend chart you want to configure.
On the Trend Chart toolbar, click Settings .
Click the Axis tab.
In In the Time mode box, select Relative .
action_zoom_plus_stroke 
In the Time span box, enter the time span.
Click OK .
The x axis is now configured with a time span relative to current time.
Trend Chart Axes in WebStation
Configuring the X Axis with an Absolute Time Span
Showing Trend Chart Grid Lines
Manually Configuring the Y Axis Scale
Automatically Configuring the Y Axis Scale
Saving Current Trend Chart Settings
Trend Chart View
Trend Chart Toolbar
Trend Chart Settings Dialog Box – Axis Tab