Trends

The Trends application allows you to work with trends that are recurring samples of data. In order to view the Trends application, you must have Show rights. If there is any change in the application rights, application refreshes and reflects the changes immediately.

Trends are of two types, online and offline.

Online Trending: In case of online trending, the trend data are uploaded continuously to the management station and are not saved in the automation station. Online trends record real-time values from your plant and display them graphically in a Trend View. The data values are sent to the Trends application upon each change of value. In case of online trending, an uninterrupted site connection with the management station is required. The measured values can be irretrievably lost when the site is interrupted during data recording. Therefore, online trend is not well-suited for long-term secure data recording. They can be used for real-time visualization of one or more process variables, usually for analysis or diagnosis purpose.

Offline Trends: In the case of offline trending, the trend data is saved locally to the trendlog object in the automation station and thereafter, uploaded to the management station either automatically or manually. The offline trend data is recorded and saved by the trendlog objects even when the management station is not connected. The automatic and manual transfer to the management station is done in the following situations:

Automatic:

When the number of defined entries is reached
When the maximum buffer size is reached

Manual:

When the data transfer is triggered by a user in the management station

The precision for a 64 bit value is supported till 2E49 (15 digits). GmsBitString64 data type is not supported.

Trends in the Flex Client allow you to view trend charts, search for trend objects, start and pause trend data display, create and modify a trend view definition, define the trends, delete a trend view definition and an online trend log object, and view quality information and missing data.

This section provides background information on Trends in the Flex Client. For mobile Flex web application, see Use Trends in Mobile Flex. For procedures or workflows, see the step-by-step section.

Trends Workspace – Tile View

Trends are located under the Application View > Trends.

In System Browser:

When you select Trends, the Trend tab displays all the related trend objects such as offline trends, online trends, and trend view definitions in a tile view.
When you select a particular sub folder, the Trend tab displays all objects present in that sub folder.

You can create new trends or search for existing trends from the tile view.

On clicking , the Settings menu displays from which you can access the Trend settings dialog box. This dialog box provides options to define the settings which are applied to trends online log objects, offline log objects and trend view definitions.

Trend Settings

The Trend settings dialog box allows you to define the settings, which are applied to trends online log objects, offline log objects and trend view definitions. In case of trend view definitions, these settings are applied only during creation of new trend view definitions.

NOTE:
Trend settings are saved per user and display the user-specific settings.

1	Data accuracy	Displays the number of samples per series, based on the selection anywhere between Loading fast to High resolution. By default, the number of samples saved is 100. NOTE: The Data accuracy slider represents 4 pixel values as follows: Loading fast saved as 1 sample per 16 pixel width. 1 sample per 8 pixel width. 1 sample per 4 pixel width. Accurately saved as 1 sample per 2 pixel width.
2	Default period	Allows to specify the time range, for which the trend data displays in the Trend View.
3	Data status indication	Select Show to display the quality indication area of rectangle shape on the Trend View. The area is highlighted with red color, in order to indicate a quality issue (a problem with the data point).

Trends Workspace – View Mode

The View mode allows you to view the complete chart preview of the selected trend view definition, online or offline trend log objects.

1	Legend	Displays information on the objects present in the trend view definition. You can specify the type of information to be displayed by clicking the Layout setting  button on the Horizontal Navigation Bar (see Horizontal Navigation Bar in User Interface Basics) and selecting the respective Text representation. Depending on the selected Text representation the following type of object information displays in the legend: Description: Descriptions of the objects Name: Name of the objects Description/Name: Name of the objects Name/Description: Description of the objects Description/Alias: Alias of the objects. If the object does not have an alias configured, then the description of the object displays. Name/Alias: Alias of the objects. If the object does not have an alias configured, then the name of the object displays.
2		Behaves as a toggle button and stops trend when you click . To restart logging trends, click .
3		Displays the chart data in the zoom mode for the selected time interval. See Zooming Data in Trends Step-by-Step.
4		Displays the trends workspace in the Edit mode.
5		Displays the following options: Delete: Deletes the selected trend view definition, online or offline trend log object. Show data status indication: Displays quality indications. See Creating and Managing Trend View Definitions > Display Quality Indication Area in Trends Step-by-Step. Manual upload: Fetches the latest data of all the BACnet trend log objects and displays in the chart. This option is enabled only for trend log or trend log multiple objects or if the selected trend view definition contains offline trend log objects or trend log multiple objects. Export: Displays the Export file dialog box, that allows you to download trend data according to the specified sampling rate in either PDF, CSV, or Xlsx formats.
6	Pre-defined time ranges	Displays the trend series according to the selected time range.

Trends Workspace – Edit Mode

The Edit mode allows you to modify the properties of the selected trend view definition, online or offline log object.

1	General	Allows you to modify properties, such as trend name or time period, for which you want the data to reflect in the chart, chart properties. See General Properties for additional information.
2	Series	Allows you to add new data points and modify the look and feel of the chart. See Series Properties for additional information.
3	Add chart	Creates new chart and adds it under Series or Axes tab.
4	Discard changes	Discards the changes that are made in the Trend view definition.
5	Save	Saves the selected trend view definition. If you add new data points to an online or offline log object, then a new trend view definition is created.
6		Provides options to save the trend view definition with a new name or discard the changes.
7	Axes	Allows you to specify the maximum and minimum range for the Left Y-axis or Right Y-axis which displays in the Trend view.

General Properties

Allows you to modify properties such as the Description and the time period for which you want the data to reflect in the chart, and chart properties.
The General tab displays following fields:

1		Displays the Save as option that allows you to create a Trend View Definition. For related procedure, see Create a Trend View Definition from Online or Offline Trend Log Objects.
2	Description	Allows you to enter the description for a trend view definition.
3	Default period	Allows you to specify the time range, for which the trend data should display in the Trend View.

Series Properties

Allows you to modify properties, corresponding to the individual trend series of a trend view definition.

1		Displays the Select data point dialog box that allows you to add one or more data points.
2		Provides options to add and remove sub charts.
3	Style	Allows you to select the appropriate style properties like Color, Width, Dash Type, Marker, and Interpolation for each trend series. See Style Properties for more information.
4	Data point	Displays the description of the data point. You can also enter a name for trend series in the text box below, which is stored as a description in the current language of the user.
5	Y-Axis	Indicates the y-axis where the data point is scaled (left or right).
6		Allows you to remove the trend series from the trend view definition only. NOTE: The online log object of the deleted trend series is retained.
7		Displays the properties of either a trended object or a trend log object in the right panel below the Properties tab, on the appropriate selection. If you reduce the size of the Series tab, the Delete option , Left Y Axis, and Right Y Axis display as menu options when you select . Additionally, the following options display: Rename: Enables the Data point section and allows you to rename the data point. Move to: Allows you to move the data points within sub charts. You can move a binary or multistate point to another sub chart, only if the point is not present in the other chart. In case of analog points, you can only move analog points of the same unit to other charts. The unit of analog points in the source and destination sub charts has to be identical. For example, you can move an analog point with degree Celsius as the Unit from Sub Chart 1 to Sub Chart 2, only if Sub Chart 2 has analog points with degree Celsius as the unit and there are less than 5 sub points in Sub Chart 2. Data point info and Show data point properties: Displays the object information such as description, name, alias, device associated with, path, and so on. The object information also displays, when you select the object in the System Browser and select the information icon  in Properties. Show in hierarchies: Navigates to the location of the selected data point in the Tree view.

Style Properties
Color
Width
Dash type
Marker
Interpolation

Axes Properties

Allows you to specify the Max or Min range for the Left Y-axis or Right Y-axis which displays in the Trend view.

1	Left/Right Y-axis: Min.	Allows you to specify the minimum range for the left/right y-axis, which displays in the Trend View.
2	Left/Right Y-axis: Max.	Allows you to specify the maximum range for the left/right y-axis, which displays in the Trend View.
3	Chart	Displays the chart added to the trend view definition.
4	Auto-scale	Displays scale of the y-axis, based on the trend series data. A minimum and maximum range must be defined if auto-scale is disabled.

Export file

Exports the trend data according to the selected sampling rate in a PDF, CSV, or Excel format.

Sampling rate

Select any of the following type to export the trend data:

NOTE: The Sampling rate options are displayed based on selected time range.

As shown in chart: Exports the trend data displayed in the trend chart for selected period.
Hourly: Exports the aggregated hourly data for the selected period. This option displays if the selected time range is between 1 hour to 365 days.
Daily: Exports the aggregated daily data for the selected period. This option displays if the selected time range is between 1 to 365 days (1 year).
Weekly: Exports the aggregated weekly data for the selected period.
Monthly: Exports the aggregated monthly data for the selected period.
The Monthly and Weekly options displays if the selected time range is between 30 to 730 days (2 years).

File type

Select any of the following file types to export the trend data:

PDF
CSV
Xlsx

Export

Downloads the trend report in the selected format.

NOTE: The aggregated data in the exported file is calculated based on the standard ISO date-time format.

Subcharts

You can have multiple charts added to the main chart of your trend view definition using Subcharts. This concept allows you to distribute the trend series with different units and with different data points across multiple charts rather than overloading the main chart. It also allows you to have a look at the multiple trend series in a common view thereby improving the readability of chart data.

Following are the features of Subcharts:

For all Subcharts, a single time bar displays. If you change the default period in the Edit mode, then the same time is reflected for all the Subcharts in the View mode.
When you zoom in or zoom out a particular area of any Subchart, then the result of the zoom operation is applicable to all the Subcharts in the trend view definition.
When you select any of the following options (hour, day, month, year, all) on the predefined time ranges in the View mode, the selected option is applied to all Subcharts present in trend view definition.
When you hide all the trend series, the Subcharts do not display any data and the time bar is hidden.
When you delete a data point from a particular Subchart, then the data point is removed from that Subchart only and not from any other Subchart. Similarly, when you add a data point to a particular Subchart, then the data point is allocated to that specific Subchart only.
You can add the below data points in one subchart considering following criteria:

For selection of data points in one subchart, select either one of the data point (analog or binary or multistate).
Maximum 10 analog data points per subchart.
2 axis (left and right together) with 1 unit value per axis for example ℃ or ℉.
1 multistate data point per subchart.
1 binary data point per subchart.

For example, assume that you have created a Subchart and selected the following combination of data points and trend log objects:

2 analog inputs with same unit (℃)
2 analog inputs with same unit (℉)
1 analog input with unit (%)
1 multistate input point
1 binary input point

Consider the above example, the number of sub charts and their points will be as follows:

Subchart 1 – 2 analog input points with ℃ as unit and 2 analog input points with ℉ as unit. This is because 1 Subchart can have a maximum 2 axis (left axis with one data point and right axis with another data point).
Subchart 2 – 1 analog input point with % as unit requires other Subchart as the unit of analog input is different and you can have only two different units in 1 Subchart.
Subchart 3 – 1 multistate input point.
Subchart 4 – 1 binary input point.

Quality Attributes

The Trend View can display a number of state attributes, referred to as quality attributes, along with the trend data. These enable you to identify problems with the data point being recorded and assist with the diagnosis of plant conditions. The quality attributes display as a tooltip when you position your mouse pointer over a trend series. Only the highest priority displays in the Trend View if several states are active. In order to display the quality attributes, you must ensure that the Show Quality option for the series to which you want to view the quality information is selected in the management station. The Trend View also displays a quality indication area of rectangle shape, which is highlighted with the red color in order to indicate a quality issue (a problem with the data point).

The following is a list of the quality attributes:

Item	Name	Description
	Error logging data	Error reading data value from the monitored object
	Reliability fault	Indicates that the value of the Trendlog object is no longer reliable.
	Faulty	Indicates that a data point error exists in the Trendlog object (values may not be usable for follow-on evaluation)
	Overridden	Indicates that the data point on a module is overridden.
	Out of service	Indicates that the Out of Service property is switched on.
	Log Enabled/Disabled	Indicates that the Trendlog object is enabled.
	Log interrupted	Indicates that the automation station has been set to state Log_interrupted in the trend buffer (for example: in the event of a power outage, application program stop, change of data point log type). This may cause trend data from not being logged.
	Buffer purged	Indicates that the buffer in the Trendlog object is deleted.
	Buffer full	Indicates that the Trendlog buffer is full.
	Time shift	Indicates that the time in the automation station was changed.
	Connected/Disconnected	Indicates that no connection exists to the logged data point.
	Reduced data	Indicates that the logged data may be huge and needs to be reduced before displaying.
	Added/Modified data	Indicates that the data has been added or modified manually.

Validation in Trends

When you set a Trend View Definition, Trend Log Online, Trend Log Offline target object with Validation profile = Enabled, Monitored or Supervised combined with the Four Eyes check box option then you are prompted to validate the actions performed to the target object.
Some examples of the performed actions are: Modify, Delete, and Manual upload (in case of Trend Log Offline object).

When the object is modified or updated, all the changes are logged into the Audit Trail log of the validated object and the object version increments are recorded and stored under the right panel, in the History tab.
NOTE: Users with OIDC or software accounts are not allowed to validate Trend View Definition, Trend Log Online, Trend Log Offline objects.

The following table displays applicable Trend View Definition, Trend Log Online, and Trend Log Offline target objects with their respective actions:

Validation Profile Target Objects	Action	Validation Output
Trend View Definition	Modify and Save Trend View Definition Delete Trend View Definition	On saving the changes, Validation required dialog box with corresponding input field is displayed based on the Validation profile.
Trend Log Online Object	Delete Trend Log Online Object
Trend Log Offline Object	Manual upload of Trend Log Offline Object NOTE: For a trend Log Offline object, when trend data is uploaded by using Manual upload button, automatic uploading of trend data is not triggered.

Following table displays some more scenarios where multiple objects are validated and their corresponding validation output:

#	Scenarios for Trend View Definition		Validation Output
1	Trend View Definition is not validated	Commanded Output (Trend Log Offline Object) is not validated	Validation required dialog box is not displayed.
		Commanded Output (Trend Log Offline Object ) validated	On modification of Trend Log Offline Object (that is when trend data is uploaded by using Manual upload button), Validation required dialog box with the highest Validation profile is displayed.
2	Trend View Definition is validated	Commanded Output (Trend Log Offline Object ) is not validated	On modification of Trend Log Offline Object (that is when trend data is uploaded by using Manual upload button), Validation required dialog box is not displayed.
		Commanded Output (Trend Log Offline Object ) is validated	On modification of Trend Log Offline Object (that is when trend data is uploaded by using Manual upload button), Validation required dialog box with the highest Validation profile is displayed.