In the screen for creating and editing a line or bar chart, you will see 3 columns. One each for the X-axis, Y-axis and data series.
Above each column there is a button for adding new elements to the respective column.
These elements can be edited and deleted either via their context menu or by pressing the Del key or double-clicking.
The graphic above shows the configuration of a simple diagram that displays the value of a single variable over time.
X-axis
There are generally 3 types of X-axes: time axes, category axes and value axes. Before going into the special features of the individual types,
Let’s start with the similarities. For the time being, only diagrams with a single x-axis are supported. The possibility of supporting multiple X-axes is currently being investigated.
- Name
Each X-axis needs a name. Whether or not this is also displayed later in the diagram can be controlled with the “Display” checkbox directly next to the input field for the name.
- Grid lines
Grid lines are the lines of the chart that start from the respective axis and simplify the reading of values on the graph.
To hide lines, simply set the width to 0.
- Color
The color of the axis line and the axis label.
Timeline
A time axis shows values over time.
The area of a timeline can be zoomed and moved. Settings for this can be found in the “Zoom & Pan” tab.
The slider is a useful tool for quickly jumping to another section of the graph. It can also be used to enlarge or reduce the area.
The displayed area can also be changed using the mouse. Here you can set whether the mouse can be used to zoom and pan, and if so, how. (mouse only, or in conjunction with another button.)
Category axis
Bar charts can be displayed with a category axis.
Categories
To understand what is meant by categories, take a look at the following graphic:
In this example, the categories are “Tank1“, “Tank2” and “Tank3“. Each tank has 2 values (Pressure and Heat) that are displayed.
Each category can therefore contain a number of bars.
Value axis
The value axis is the last of the supported X-axis types and allows 2 values to be displayed against each other.
For example, the change in temperature due to pressure changes.
The special feature of the value axis is that a value range can be defined for it. According to the standard setting, all axes always adapt to the displayed values.
They are therefore dynamic and change their value range. If you want to prevent the axis from changing its value range, it is also possible to define a static value range.
The options for zooming and panning are the same as the timeline.
Y-axes
- Name
As a diagram can have any number of Y-axes, it is important that these are clearly named. If a name already exists, you will be informed of this when saving.
The “Display” checkbox can be used to specify whether the name is also displayed later on the diagram or not.
- Position
The position determines whether the Y-axis is displayed on the left or right side of the X-axis.
- Range
Just like the X-value axis, the value range of the Y-axis can also be defined. By default, all axes always adapt to the displayed values.
They are therefore dynamic and change their value range. If you want to prevent the axis from changing its value range, it is also possible to define a static value range.
- Color
The color of the axis line and the axis label.
- Grid lines
Grid lines are the lines of the chart that start from the respective axis and simplify the reading of values on the graph.
- Zoom/Pan
An explanation of the setting options for zoom & pan can be found under “Timeline“. The settings for this are identical.
Data series
The setting options for individual data series depend on the selected X-axis type.
In the following part of the documentation, please note which options are available for which types.
- Name
The name of a data series must be unique within a chart configuration. This name is displayed in the legend.
- X-axis
Indicates the X-axis to which the values of this series refer.
- Value (only for X-axis type “value“)
Specifies which value of which variable is plotted on the x-axis.
- Y-axis
Indicates the Y-axis to which the values of this series refer.
- Value
Specifies which value of which variable is plotted on the Y-axis.
You can change the appearance of the data series in the Lines tab. The maximum amount of data per series can also be limited here.
The “Width“, “Color” and type of line (“type“) can be selected. You can also decide whether the area under the lines should be filled or not. Use the checkbox for this.
You have the option of displaying faulty values separately. This could be a missing connection to the PLC or variable values of poor quality, for example. To do this, activate the“Highlight” checkbox and select a color. The incorrect values are then displayed as a line in the selected color.
An overview of the different types of lines
The “data limit” is the maximum number/age of data points.
These settings are used to reduce the amount of data in the charts. Too much data can affect the performance of the viewer.
By default, both a time limit and a quantity limit are set. Whichever limit is reached first will result in data points at the start of the series being deleted. If the limits are set to “0“, this removes the limit.
The “Markers”, which mark the data points, can be customized in the lower area. Both in “Size” and “Type” (or shape).
To hide the markers, the size can simply be set to “0“.
The ” Showvalue ” tick controls whether the respective values should also be displayed on the markers.
