Working with data files

This section describes how to download data files from the LI-8250 and the contents of those files. The LI-8250 creates two types of files: daily summary files and raw data for a single observation.

Daily summary files: Data that summarizes each observation for a day can indicate if the system is working properly. File names for summary files are formatted with the instrument serial number and date (serial-number-YYYYMMDD_dense_summary.csv). Daily summary files are .csv files that summarize fluxes, means, and initial values to represent a subset of all available variables in the system (see ). These files include a header made up of 3 lines: the source of the measurement (e.g., LI-8250), the variable name (e.g., DATE), and the units for the variable (e.g., YYYYMMDD)

Raw data files: Raw data for a single observation are stored in compressed text files with a .82z extension. These files are for use in SoilFluxPro Software to simplify the management and processing of large soil gas flux datasets. Raw data file names are formatted with the instrument serial number and a time stamp (serial-number-YYYYMMDDHHMMSS.82z). These files include all measurements at a given port for one observation.

When uncompressed, raw data files expose two component files: a data.csv file and a metadata.json file. The data.csv file uses the same 3-line header structure as the daily summary files but includes raw time series data from one observation with every variable collected by the system. See the tables in Data dictionary - measured variables for a complete list of variable definitions. The metadata.json file is a text file containing all the observation, instrument, and flux calculation metadata (also described in .

Note: Raw data files do not include fluxes or summary values for any variable.

Downloading files

You can retrieve files from the LI-8250 Multiplexer in three ways:

  • Download directly from the user interface
  • Transfer to USB storage from the user interface
  • Automatic transfer to a remote server

Download from user interface

To download the files from the LI-8250 Multiplexer user interface:

  1. Connect to the LI-8250 Multiplexer user interface.
  2. Go to the Files page.
  3. Select a Start Date and Time and an End Date and Time for the range of files to download.
  4. Click the Download button.

The daily summary files and .82z files will then be downloaded to your device as a .zip file. The file name will use the serial number, the start date and time, and the date and time of download (serial-number-YYYYMMDDHHMM-YYYYMMDDHHMM).

Opening the .zip file will provide all the summary files for the dates in range and a directory. The directory contains all the .82z files separated into subdirectories, first by year, then month, then day.

Transfer to USB storage

To transfer files from the multiplexer to a USB storage device:

  1. Connect to the LI-8250 Multiplexer user interface.
  2. Go to the Files page.
  3. Select a Start Date and Time and an End Date and Time for the range of files to download.

  4. Insert a USB storage device into one of the two USB ports on the multiplexer interior panel.

    The USB storage device must be connected to the multiplexer. The user interface will not recognize a USB device connected to your computer.

  5. Click the USB button.

The daily summary files and .82z files will then be downloaded to your device as a .zip file. The file name will use the serial number, the start date and time, and the date and time of download (serial-number-YYYYMMDDHHMM-YYYYMMDDHHMM).

Opening the .zip file will provide all the summary files for the dates in range and a folder. The folder contains all the .82z files separated first by year, then month, then day.

Automatic transfer to remote server

The LI-8250 Multiplexer can be configured to automatically transfer daily summary files and .82z files containing raw observation data from the previous day to a remote server using FTP, SFTP, or HTTP. This will require the multiplexer to be connected to a LAN or cellular modem via Ethernet.