Description

This tool allows you to group several COMTRADE files from several versions to combine their signals and produce a single file. It can be accessed through the signal selection window, in the top bar by clicking on Tools.

Open

Menu to access the combiner

The combination is done with predetermined parameters to adequately select the desired data. Among these parameters, we find a start and end time in milliseconds, a new sampling rate, the type of interpolation chosen if re-sampling must be done, and the COMTRADE version produced.

It is divided into four sections related to the following image interface:

• Section 1: Contol

• Section 2: Settings

• Section 3: Min/Max comtrade values

• Section 4: Selected Files

Open

The combiner and its sections

Section 1: Control

To add multiple files, the user can select a parent folder and all COMTRADE files under that folder is added. To have a better overview, the user can group their COMTRADE files by acquisition types in individual folders under a parent folder:

When selecting the parent folder, all subfolders are read and COMTRADE files are added to the table.

The combiner allows the selection of desired signals from the list of all signals in the added files. To open the menu, the Signal filter menu... button must be selected. This menu has two tables and buttons. On the left, we find the list of signals for all the added files:

When no signals are selected, the combiner chooses all available signals. To select signals, choose them individually from the table on the left. It is also possible to search for a specific signal in the list using the text field below the table, in addition to being able to select several at once.

To remove items from the right table, select them and press the Remove Selected button or the Delete key on the keyboard.

Section 2: Settings

All settings to create the combined COMTRADE file is here. Choosing parameter values applies a filter to select all signals that meet the desired conditions.

Example

If a user wants to combine several small successive acquisitions into a single file, he has to set the start time of the first acquisition and the end time of the last acquisition to filter the good signals.

5 files represent the continuation of a 23-millisecond acquisition. Currently, these files are independent acquisitions in ScopeView. Their start and end times are the same since the files only represent the time-space of their acquisition:

If these five files are added to the combiner, their adjustments to real space-time can be made. This means that the signals are referenced according to the start time and the end time indicated in the settings. Using the Maximum Values button (from the next section), a user can enter these parameters automatically:

After the combination, the signals from all five files are centered on the new time reference.

Therefore, it is possible to see the sequence of signals, according to their true time reference, using the superposition in ScopeView:

Section 3: Min/Max comtrade values

This section has non-editable fields and a button to apply them. These fields represent the maximum information that can be put as parameters. The minimum time represents the signal among the added files, that has the most recent start time. The maximum time represents the opposite, the oldest time among the signals. Additionally, the highest sampling rate value is present, to allow all signals to be adjusted to the same. This section is used to quickly encompass and include all signals from files that are added to the combiner.

It is important to note that for performance reasons, combinations are limited to a maximum of 60 minutes.

Additionally, a Set selected row button is present to apply the settings of the selected file in the table. When pressed, the settings of the chosen files are now the combination settings. This feature is useful when a user wants to target a specific file among the others.

Section 4: Selected Files

When adding a COMTRADE file, several information and fields are displayed in a new table row:

Synchronizing Files

Some COMTRADE files may have minimal delays, which negatively affect signal analysis. These delays are in the form of a few seconds or less. To compensate for these delays automatically, a tool has been added to provide the exact value in the offset column of the table. Synchronization is done in a few steps.

You must first select the reference file. This file is selected with a click on its row in the table of added files. When selected, the row is highlighted in blue. This subsequently allows any synchronization to be based on this file and its parameters. The sample rate can also be adjusted, it defaults to the average of added files, but it can be lowered to reduce file size.

The timing menu can be opened by selecting the Calculate delay button. This menu displays a list of signals by files to synchronize. The signals on the left are the signals from the reference file chosen earlier and on the right are the other files in the table that have been added. The tool tries to link signals that have names with similarities, but if nothing is found, the first signal in the list is selected. At any time, the user can change the signals to be used for synchronization.

The tool determines the delay between the chosen signals and the reference one using algorithms. Any delay found is subsequently added in the offset column to the added files. It is then necessary to combine everything to have the deadlines applied. If the signals are already synchronized in time, the returned value is 0.0.