Calibration and maintenance

The LI-560 requires very little maintenance. The sensor can be user-calibrated, as described below. The firmware can be updated as well.

User calibration

Every LI-560 is tested and calibrated prior to shipping.

However, you can re-calibrate the sensor to acclimate to unique use cases or local conditions by following these directions.

Anemometer calibration

Place the LI-560 inside a small container to reduce the airflow to as close to zero as possible. Care must be taken to eliminate acoustic reflections from hard sides and to not block the acoustic pathways. There should be some sound absorbing material on any flat walls that could reflect sound back towards the LI-560. A small box with acoustic absorption foam is ideal. However, in a pinch you can successfully calibrate a LI-560 by loosely wrapping a coat or towel around it. The main thing is to provide a zero-wind environment, and to know the temperature, and ideally the humidity, of the air volume where the LI-560 is enclosed.

At the command line interface, type calibrate <temp> [<rh>] where <temp> = xx.x in °C temperature and <rh> = xx.x in % relative humidity. If humidity is not supplied, then 50% is assumed.

  • Example: Sending calibrate 32 25 will adjust the temperature measurement to read 32 °C and the relative humidity measurement to read 25%.
  • Example: Send calibrate 32 to adjust the temperature measurement to read 32 °C and adjust the relative humidity to an assumed value of 50%.

The calibration cycle takes ten seconds. You will see dots printed on the serial console indicating progress, and the serial prompt will return when the calibration is completed. Enter nvwrite to store the new calibration values in non-volatile memory.

Level calibration

The calibration function of the level is simply an offset adjustment for the accelerometer inside the LI-560. Place the LI-560 on a known upright pole so that the shaft of the LI-560 is perfectly vertical. With the LI-560 in this known level configuration execute the levelcalibrate command. Enter nvwrite to store the values in non-volatile memory.

Recovering from a bad calibration

If, after calibrating, the readings are not correct, reset the instrument to factory defaults in Expert mode, then try to calibrate again. Be sure to exit expert mode before storing the new calibration to non-volitile memory using nvwrite.

Firmware updates

Firmware updates will include bug fixes and feature improvements.

Updating firmware

You can download the latest firmware release at Save the program to your computer. Connect the LI-560 to that computer. From this point, choose a method of command access (Tera Term is offered as the terminal emulator example):

Using the LI-560 application:

  1. In the Settings Tab click Browse…
  2. Navigate to the downloaded file.
  3. Click Update Software.
  4. The LI-560 updates and the new version number will register on screen.
  5. Perform a user calibration (see User calibration).

Using Tera Term (terminal emulator):

  1. With the LI-560 connected and streaming data, press CTRL+C.
  2. Type programupdate YES.
  3. From the Tera Term menu select the following: File > Transfer > YModem > Send.
  4. Select the file to upload and press Enter.
  5. Perform a user calibration (see User calibration).

Updating the bootloader

Two programs reside in the internal memory of the LI-560: the LI-560 application and a bootloader. During a reset or power on, the bootloader checks to determine if the LI-560 application is valid. If the sensor application is valid, the bootloader turns over control to the sensor application. If the sensor application is not valid, the bootloader shows a command line interface with a limited set of commands: help, programupdate, systemreset, and factoryreset. These commands perform the same functions described in Support: LI-560 TriSonica® Sphere Ultrasonic Anemometer.

Follow these steps if you need to update the Bootloader:

  1. Update the LI-560 application.
  2. Enter the command line interface.
  3. Enter the expert mode with the command expert enable.
  4. Enter the command bootloadupdate YES to update the bootloader.

Cleaning the sensor

To clean the LI-560, wipe with a clean lint-free cloth dampened with distilled water, then dry with a dry lint-free cloth.

Wipe gently to avoid removing or dislodging any of the sealants on the spherical arms or the assembly joints.