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Datasheets and User Guides

Software & Driver

 

Data Logging and Viewing

LJLogM is capable of generating customized log files that can be easily imported into spreadsheet tools such as OpenOffice, Excel, or any other post-processing tools. There are settings to customize the file name, data formatting and optional data. After data has been logged, users can go to the tab "5. View Log Files", where they can find a list of the generated files and there are application short cuts to open the files in OpenOffice or Excel.

Write to File: This control starts and stops data from being logged to a file.  When it is illuminated light green, data is being logged to a file.  There is program indicator at the top of the application that that also displays this.

Not Logging Logging

Current Data File: When data is being logged to a file, this indicator displays the current file path and name of the file being logged to.  There are buttons here that let users force a new file to be created, re-configure LJLogM to change directories where data is being saved, and a button that lets users open Windows Explorer at the directory where data is being logged.

Log Rate: LJLogM can be configured to save data at a different rate than data is collected.  When Log Rate is 1, data is logged every data collection interval.  When log rate is 2, every other value gets saved, etc.

Max File Size (Bytes): When the current data file exceeds this limit, the file is closed and a new file is started.

Log File Naming Settings

The file that gets generated during a logging session by LJLogM can be customized by defining a "File Name Format String" which can include bracketed strings/keys that get replaced by the applicable referenced device settings or a time string.  At the end of the file, a file counter string "_0" is added which gets incremented each time a new file is created due to its size getting to large ("_1", "_2", etc).

To create the list of files:
data_0.dat
data_1.dat

Use the settings:
File Name Format String: "data"
File Ending: "dat"
{{time}} Format String: N/A

To create the list of files:
data-20180812_0.csv
data-20180812_1.csv
data-20180812_2.csv

Use the settings:
File Name Format String: "data-{{time}}"
File Ending: "csv"
{{time}} Format String: "%Y%m%d"

Log File Data Formatting Settings

LJLogM also has a variety of settings to customize the data that gets logged to a file.  As settings get enabled and disabled, a file-preview window is updated to reflect what data is going to be saved to the file.  There are these options to customize:

Data Delineation: Data is saved into a file with standard CSV (comma-separated values) formatting.  Rows are terminated with a newline ("\r\n"), and columns are separated by comma (","), tab ("\t"), semi-colon (";"), and/or space (" ").

Spreadsheet Header: A header section can be optionally included or excluded from the generated file to save space and make it easier to parse data with post-processing tools.  The "On New File" option lets users choose whether or not the header data is added.  The "Save Data Group Name" is an option to include or exclude what data group each of the values were associated to.

Additional/Optional Data:

  • Log Timestamp: When enabled, a timestamp is logged for each interval.  The timestamp can be customized by editing the "Data Time Format String" field.
  • Log Raw Data: When enabled, the raw value for each register is logged to the file.
  • Log Scaled Data: When enabled, the scaled value for each data point is logged to the file.
  • Log Error Code: When enabled, the LJM error code returned by the LJM_eReadNames function is logged.
  • Log Num Disconnects: LJLogM keeps track of how many times a device has become disconnected and re-connected.  When enabled, LJLogM will log this value.
  • Log Alarm Status: When enabled, LJLogM will save a boolean "Yes" or "No" value (1 or 0) to indicate whether or not there was an overall alarm condition triggered due to one of the scaled values being to high or low.
  • Log DAQ Latency: When enabled, LJLogM will save the time between log intervals to the file which makes some post-processing calculations easier.

View Logged Data

After generating data log files, LJLogM can help users find and view the generated files by running some Windows command prompt commands.  The list of log files that have been created can be filtered by the drop-down menu.  After selecting a file, users have the option to:

  • Open the file in its default application.  This is set in Windows settings.
  • Open the directory of where all of the logged files have been created.
  • (If installed) Open the file in OpenOffice.
  • (If installed) Open the file in Excel.