NOTE: Bazefield Portal 8.6.1 and newer releases can follow asset time zones. This will impact the explanation here

Use Case

Bazefield 8.0.25.6 

Understanding the Data Export application's options and exported data's timestamps. This article describes how the application handles different time zones at the buffer layer and end user's own computer (exporting data from Bazefield's Portal).


Background

The User's computer's timezone affects the displayed 'time periods' seen in the portal.

The local time zone is used in certain other applications like the Alarm Log to display a local time view of the application.


! The data engine itself stores data in UTC time zone (historian).


You may prefer to export data in the UTC format, an option in the Data Export tool. 
The core server functions operate in the data engine servers timezone..


Data Export Example

*The User's Computer browsing the Bazefield Portal is in the Pacific Time Zone. An example wind site is located in Mountain Time.


Note: If an aggregate is used, Bazefield displays "Hour Beginning" values. For instance, data values from a 1 hour average aggregate type displays a timestamp of 00:00:00 for data from 00:00:00 to 00:59:59.


Current data on the portal is a few seconds behind "now" in my Pacific Time zone, i.e. 10:03 AM shown below (the natural data transfer period from site to portal view).



Inside exported data file, the data is timestamped in the site's timezone because this is actually a "core server function" that is operating on the server, not the portal. 

In this example, the site's server is 1 hour ahead (11:08AM) of the user/portal computer (10:08AM). Mountain time vs Pacific. With the UTC option disabled, we see the data exported below:



The data export tool requires you to specify a time range, notice the selection in the filter pane for 'From' and 'To'.
If you wanted to look at data on March 15, how should we interpret the timestamps upon export? 

If the wind site is going to be in the same timezone as the site server, you should be able to leave UTC off (using server time) and ask for the data for 3/15. It is received as site time.



Attached is a raw values export of substation data -- what we observe here is a 3/15 3:33:11 (site time) site trip shown by the substation active power tag. Again, the portal is in your own timezone.




Comparing the timestamp at the very beginning of the export to the beginning of your requested Data Export 'From" timeframe from the Portal can be helpful/


Choosing a "From" time in the Data Export App will take the time from your own machine and (with UTC disabled) pulls out data that is consistent with the server's timezone (a server core function).



Summary

  • The User's computer's timezone affects the displayed 'time periods' seen and used in the portal.

  • ! The data engine itself stores data in UTC time zone (historian).
  • You may prefer to export data in the UTC format to easily make comparisons or troubleshoot issues.
  • The core server functions operate in the data engine servers timezone which, in this example, is Mountain time.