Set Continuous SDI-12 Mode on Vaisala WXT53x Weather Station

*For connection with iSIC data loggers

The only manual configuration that needs to be made to the WXT53x stations is the enabling of Continuous SDI-12. These WXT 530-series stations (as of mid-2019) have an issue with their Native (default) SDI-12 mode. During precipitation events, they can fail to wake up from sleep mode and are unresponsive until power is cycled.


Set Continous SDI-12 Mode

  1. Install/Open the iChart software on a PC.
    1. Install iChart
    2. Register iChart


  1. Connect the iSIC data logger to the PC containing the iChart software either directly (recommended), or over other working telemetry options (e.g. cellular, radio, etc.) on the iSIC data logger.


  1. Ensure the Vaisala weather station is connected and adequate power is applied to the data logger.


  1. Click Advanced | iSIC | iSIC. The iSIC Setup window should appear.

iSIC setup window


  1. Enter the correct connection type and iSIC or SDL address. If connecting directly to the iChart PC, make sure the correct COM Port is selected.

Available connection types for multiple iSIC logger models.


  1. Click Connect.


  1. Select the General tab to allow the iSIC’s configuration to be read.



  1. Select the SDI-12 tab.

SDI-12 tab


  1. To find the sensor’s SDI-12 address and confirm sensor communication, type this command:



Address query command


    • A result in this format should appear:



    • Note: “a” is used as an example address above. Record the sensor’s actual address. It will be used in sending other commands.


  1. Ensure that you are communicating with the correct sensor by inputting the identification command:




SDI-12 Identification Command


    • A result should appear in this format:

“allccccccccmmmmmmvvvxxx . . . xxx <CR><LF>”

    • Note: “a” is used as an example address above. “ll” is the SDI-12 version number indicating SDI-12 version compatibility. “cccccccc” is an 8 character vendor identification. “mmmmmm” is the sensor model number. “vvv” is the sensor version. “xxx…xxx” is an optional field, up to 13 characters” used for a serial number.


  1. Verify Communication Settings with the aXU! command

Check communication settings. “M=S” means the Vaisala is in native SDI-12 mode.

    • [M]= COM protocol, S is Native SDI-12 and is Continuous SDI-12


  1. Set Continuous SDI-12 Mode with the aXU,M=R! command

Set Continuous SDI-12 mode


  1. Verify the change by sending the aXU! command

Successful change to continuous SDI-12 mode.



  1. The Vaisala WXT53x weather station should now be set for Continuous SDI-12 mode.