ContextHub - Context items

What is a context Item? 

A context Item is a block of information linked to a data point or a period of data associated with an event identified in your datasets. Instead of writing a note in a book, add your thoughts and observations to a context item. 

Why use a context Item?

Having created your context item, you can use it to compare with other context items, share insights with colleagues and add further contextual information that will strengthen understanding of your process.

Context items can be added to the graphical representation of your data, or within contextHub.

The Context Item Menu

The Context Item menu shows an overview of all context within the focus time range of all visible tags.

  1. Select the Tags icon tag.png and add tags to the active tags list in your TrendHub menu, to see trendlines in your focus chart.
  2. The Context Item icon context_image.png will now display on the TrendHub menu; click on it. Once selected, the Context Item menu is revealed


Context items (previously known as annotations) in TrendMiner are, for example, descriptions of events or asset issues. You can use context in TrendMiner to label interesting or notable occurrences attributable to your processes. Context can be thought of as text balloons used to label your trends.

Note: The Context Item menu lists a maximum of 150 context items. When more than 150 Context Items are available in the focus range a feedback message will be shown and no Context Items will be plotted or listed anymore. To show context items again you zoom in on the focus chart or zoom in on a smaller time frame.

All context items are stored and managed in ContextHub.

Like metadata, context can be searched and filtered in TrendMiner to help you find the events or assets of interest to you.

Context items

There are two types of context items:

  1. Instant context
    • A single point in the focus chart added instantly via a side panel - a context balloon is created.
    • These point items indicate a single time stamp of interest (no duration); for instance a remark or an info message.
  2. Context item event(s)
    • These indicate time periods of interest, for instance a faulty condition or a maintenance activity that have a start and end timestamp.
    • Context for which both a start and end time appear in the Context Item menu, was previously described as an event frame.

How to create context items

Context items can be created in the focus chart, and later retrieved in ContextHub. In order to create instant context:

  1. Double click in the focus chart where you wish to create context. A data scooter will appear.
  2. Click on the three vertical dots button within the data scooter. A short drop down menu will appear.


  1. Click on the "Add context item" option.

An "Add context item" side panel will appear from the right of the screen.

  1. Select the component (tag, attribute or asset) on which you want to create the context.
  2. Select the type and description of the context.

Optional: Assign keywords and/or a description to the context.

  1. Tick off "Create item on visible layers" if you want to create context for all layers present in the focus chart.

This could be useful when you have retrieved multiple occurrences of a similar event and want to label all the overlays with one action.

  1. Click the 'Save' button.

Note: When creating context over a period in the focus chart, the scooter will present range information that highlights the start and end of your selected period. On the chart two icons for this item will be displayed, highlighting the beginning and ending of the event.

Note: When working in stack plot, the item is set by default to the first tag in the list. This can be changed in the side panel.

How to view context details

Under plot settings, click on the option for "Context items". This will display the items you have in your plot. If this setting is not turned off, no item will appear in your plot. If you have many items in your plot, it can be useful to turn off this setting so that you have a clear view of your charted data.


To check context item details:

  • Click on the context item icon in the plot. or;
  • Open the context item menu by selecting the "Context Item" button in the TrendHub menu. Click on an item or item icon in the menu.

In the context item menu the items display item type (title and icon), start and end time of the context item, tag or attribute name. The items are date ordered.

Note: The context field can be displayed under the context type, if the context type is linked to this field and the option "set value as label" is turned on in ContextHub.


In both these instances a side panel will appear from the right of the screen. The panel contains the context already created for the item.


In the newly opened context panel you can add further context to your item, including;

  • Attachments
  • Comments

If your item is a period event, you can also identify the period durations of each event within your context item panel; both numerically and visually via a blue bar. This duration information is very useful when targeting cycle times, for example batches that took longer than 2.5 hours. The size of each bar segment correlates with event duration; total duration being the sum of all events in a given process, is also available.

Note: Normally, item duration can be used to filter and sort your context items in both grid and Gantt views; as well as your context views.

Note: When a grey area is selected and a context item added, two context item icons appear. One at the beginning of your selection and one at the end.When you hover over the first of two paired items the intervening period is highlighted over the rest of the trendplot. This feature is particularly useful when your chart is filled with context items.


How to search for context items

You can search context Items in two different ways; Whilst within ContextHub, and by selecting Context Item saved views under the search icon (where you are directed to the work organizer). That search can be saved as a ContextHub view and that view can be used to search for time frames defined by the start and end event of the searched context items (or a small time frame of a few seconds starting at the start event of an instant context item).

How to filter context items

A filter field is available in the Context Item menu. Type a search string here to filter context items based on their type, plant component name, or description. Context will be filtered in the list, as well as on the chart. In the example above, all 'operational' periods have been filtered. Context Items can be filtered and saved into Context Hub views.

ContextHub views can be used to search specific periods of time via a context item search. These search results can then be used for overlays, comparison, fingerprint creation, etc.

How to visualize context items 

This option will zoom the view to the timeframe of the context item, and make all tags that were selected in the visualize panel visible in the view.  

When context items have been created, it is possible to later visualize them.  

  1. Click onto a context item, the context item side panel will appear from the right. 
  2. Click "Options" drop down. 
  3. Click "Visualize", the visualize panel will appear from the right.  

Note: In the visualize panel, the list of selected tags and attributes appear that can be hidden or removed. In addition, a list of recently used tags, attributes and views are displayed for convenient addition to your opened context item. 

How to delete context items

Deletion of context items can be conducted in two ways; through ContextHub and through the Context Item menu.

  1. Navigate to the time period where you want to delete context items (only context items present in the focus chart will be listed).
  2. Open the Context Item menu.
  3. Select the Item you wish to delete, a side panel will appear from the right.
  4. Click the options button then select delete.

Context items on tags

In TrendHub, when adding a tag to the active tag list, the context items of the tag are visualized. When adding attributes via the asset browser, context items on attributes and their direct ancestors are visualized, next to the context items which are made directly on the linked tag.

The following example shows an attribute "Temperature", an attribute of "Reactor 1", linked to the tag BA:TEMP.1


In this case, context of Reactor 1, Temperature and BA:TEMP.1 will be visualized on the chart.


The next example shows a tag BA:TEMP.1 in the active tag list. In this case only context items of BA:TEMP.1 are visualized. 

How to manually resync context items 

Context Item resync 

You can actively refresh context items from the source system if you believe that something went wrong, for example, the context data got corrupted or becomes outdated. 

​At any time, you can align details of your context items with your source data, via the detail panel of any context item that originates from an external source system. When you decide to resync, a source system check is conducted to identify any updates on the original event frame. Any new updates will be identified, and then reflected into TrendMiner.

To resync an item: 

  1. Open a Context View. 
  2. Select a context item and open the details panel. 
  3. Click on the "Options" button. 
  4. Select "Resync".


Bulk resync

There is a bulk resync option available to ContextHub Administrators. This can be done within a ContextHub view, in table mode.

  1. Click on the check boxes of the items of interest in a Context View.
  2. Then click on the "Resync" button located at the base of the table. A pop up will appear.
  3. Click on the "Proceed" button.


Note: Resync jobs completed are highlighted in the notification center. Notifications will emphasize whether a synchronisation succeeded or not, and whether items were deleted or updated.





Enjoying TrendMiner? Share your experience to help the community.
Rate TrendMiner