In this document
We will show you how to work with the time reference quality control tool of the Analyst application.
Time reference checks (TRC) must be performed first to ensure all data is correctly aligned with the timeline. Without this step, subsequent checks, such as solar radiation validation, may produce misleading or inaccurate results. Automatic quality control tools require the data to be in UTC-0 and aligned to the center of the measurement interval. The TRC tool ensures this consistency by removing any time zone differences, daylight saving time shifts, or shifts introduced by the data logger.
Key points to remember:
The dataset must contain solar data to perform the time reference check.
The TRC modifies measured data, and by correcting timeshifts, it may result in the loss of some measured values due to overlapping with others.
Automatic time reference checks are available for GHI and GTI parameters only, and GTI must be properly configured using the Metadata editor.
If your dataset does not contain GHI and GTI parameters but contains other solar parameters (e.g., DNI), you can still create manual time referecne checks.
Zooming the chart also considers the selected height as well. You can use this advantage when selecting data range with low values which would otherwise appear close to zero in the chart.
Time reference check tool
You can open the time reference check tool from the main menu via Quality/Time reference or by clicking the 
icon located below the main menu. The window interface offers the following:
KT original/KT shifted charts: These visualize the data alignment before applying the timeshift and after. The more they match, the more the data is aligned with the correct timeshift (blue vs red).
Timeshift visualization: This chart shows timeshift ranges and their confidence levels (after auto detection).
Time series chart: Shows the timeline of the compared data before and after the shift with a calculated clear-sky curve. The charts should be aligned when all timeshifts are removed.
Solar parameter selector: Select the parameter you want to compare or autodetect.
Timeshifts window: Displays all time shifts created in the time reference check tool. If there were any timeshifts previously configured or applied during the dataset import process, these will be displayed in a different window above this. You can activate/deactivate any time shift to see its impact (redraw required). Text color indicates the confidence level (autodetected time shifts only).
Timeshift editor: Edit the selected timeshift here. Also provides a “Redraw” button to visualize any changes.
Time reference check saver: Use “Save” to save any changes when you want to return and continue correcting the timeshifts, and “Final save” to save the changes and add time reference QC status to the dataset, indicating the time reference has been completed.
Tips:
To visualize changes you have made in the charts, use the “Redraw” button.
Redraw only changes the visualizations, it does not save any information to the dataset.
You can save your progress anytime using the “Save” option at the bottom-right.
Removing the timeshifts
The timeshifts are usually set and removed during the dataset import. If there are still any inconsistencies, the time reference check tool will help you to identify them and make necessary amendments. The time reference check can be executed automatically or manually.
Automatic time reference check
If your dataset contains GHI or GTI solar parameters, you can execute automatic time reference check. It will try to detect the timeshifts across the dataset, set them, and provide a confidence level for each in the timeshift visualization chart.
Executing automatic time reference check
Select the parameter you want to perform the check for (GHI or GTI).
Click “Auto detection” to execute it.
Once the autodetect is finished, identified timeshifts will be added to the timeshift list and visualized in the timeshift visualization chart for reference. The confidence level per timeshift is also indicated - by the text color in the timeshift window and the orange area in the visualization chart.
Green timeshift text color - very high confidence, the timeshift is very likely to be accurate (< 5 min).
Yellow timeshift text color - medium confidence for the correct timeshift detection (5 to 8 min).
Red timeshift text color - lower confidence for the correct timeshift detection (> 20 min).
Tip: You can decide which autodetected timeshifts to apply using the checkboxes.
Manual timeshift setup
You can add timeshifts manually using the provided timeshift editor.
Click the “New'“ button.
Set the from/to date range where the timeshift should be applied.
Set the timeshift (in minutes).
Click “Redraw” to visualize the changes.
Importing timeshift from a reference dataset
If you have a reference dataset with correct timeshifts for the given location, you can use it as a reference and apply it to your dataset. The imported dataset timeshift will be added to the time shift window, where you can apply it to the dataset.
Click the “Import” button.
Select a dataset from the list and click “OK”.
Finishing time reference check
Once you are done with the time reference checks and you are satisfied with the timeshift alignments, use the “Final save” button to apply the changes and mark it as finished.