Whenever you first connect to your LI-8250 Multiplexer you will find yourself on the Home page. This is the primary page you will interact with and consists of four major panes.

  1. The Multiplexer pane is where you will begin a sampling sequence and receive information about the status of the sampling sequence, including which port is active in the sequence, what phase the sequence is in, and the percentage of the sequence that is complete.
  2. The Real Time Variables pane allows you to search for and select which variables you would like to monitor and provides real-time updates to those variables.
  3. The Graphs pane provides real-time graphing of the variables you selected from the Real Time Variables pane.
  4. The Device Network pane provides an overview of your networks, including configured and non-configured devices and their status.


The Multiplexer pane is also made up of several separate components.

  1. Start is where you can start or stop a sampling sequence. The sampling sequence will run as configured until you choose to stop it.
  2. Active Port will display the port that is currently being sampled.
  3. Measurement shows the current status of the sampling sequence. Preparing is when the chamber is closing, Active is when a sampling sequence is in progress, and Idle indicates that a sampling sequence has not been started.
  4. Observation Phase indicates where the current observation is according to the configuration. A sampling sequence may be Active while the observation may be in a Waiting phase. Other typical phases include prepurge, postpurge, chamber closing, delay, and observation.
  5. Sampling Sequence indicates what percentage of the sequence is complete at this time. This section also provides an estimate of the time complete and the total time of the sequence.

Real Time Variables

The Real Time Variables pane lets you select from multiple variables provided by the LI-8250 Multiplexer, LI-COR long-term chambers, LI-COR gas analyzers, and sensors to view them in real time. Selecting a variable from the drop-down menu will add that variable to your Real Time Variables list and clicking on the trashcan will remove the variable. You can change the order of your variables by clicking and dragging them to a different level in the list.


The Graphs pane allows you to add any of the variables from your Real Time Variables list (up to two at a time) to graph the variable in real time. To graph a variable, click anywhere on the variable. The variable will turn gray and will begin being graphed in the Graphs pane. Clicking on the same variable again will deselect it and remove it from the graph.

The Graphs pane will only allow you to plot two variables at a time. To replace one of the variables in the graph, delete one of the variables being plotted. Then add the new variable you would like plotted.

Device Network

The Device Network pane gives an overview of the devices that are currently connected to your network. This pane will also show the different states of instruments.

Green icons indicate normal operation.
Yellow icons indicate that there is a problem.
A red icon indicates that communication between the LI-8250 Multiplexer and that device is not established.
A circle with an exclamation mark indicates a conflict between what device is connected to the port and how the port is configured in the user interface.

Hovering over a green chamber icon will provide you with flux readings from that chamber, while hovering over yellow or red icons provides you with some information about the issue with that device. Visiting the Diagnostics page can help you learn more about these issues.

The LI-870 CO2/H2O Analyzer, 8250-01 Extension Manifold, and 8200-104/C Long-Term Chamber icons are automatically added to the graphic once the data cables from those devices are connected to the LI-8250. Trace Gas Analyzers are added by connecting the tubing and data cable between the Trace Gas Analyzer and the LI-8250 (see Gas analyzers), and then adding the block and selecting the Trace Gas Analyzer hostname. See Configuring the LI-8250 Multiplexer block.