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Reply To: Keller CTD Sensor

Home Forums Environmental Sensors Keller CTD Sensor Reply To: Keller CTD Sensor


    Great – I’ve asked https://www.instrumart.com/ if they plan on stocking it.

    Something to note, a bit strange, is it comes up in SDI-12 mode, and needs an initial configuration to switch to RS485.
    From getting some initial success – it may be worth starting with SDI-12 and getting some responses. Alternatively talk with a tech rep as to how they see this can be configured to RS485 before purchase.


    Then in the Manual https://download.keller-druck.com/api/download/yRqtkpbcVNQDHa3i7zdXDm/en/2020-04.pdf
    As well as the standard RS485 interface, which provides access to
    all configuration registers, the pressure level transmitter can also be
    ordered with an SDI-12 interface. Only one interface will be active at
    any one time. Corresponding commands are used to switch between
    interfaces (default setting on delivery: SDI-12).

    From SDI12 manual ~ https://download.keller-druck.com/api/download/KMkeowTYmcRcUyZfadRVvZ/en/2015-11.pdf
    7 Switch to RS485 (Kellerbus)
    It is possible to switch from SDI-12 mode to the Kellerbus-mode (RS485 communication, Kellerbus or MODBUS RTU):
    Description Command Response
    Switch to RS485 (Kellerbus) aXC! aXC02Fe13! aXCD<CR><LF> (successful)
    aXCE<CR><LF> (not successful)
    After this command it is not possible to communicate over SDI-12 bus with the transmitter any more.
    Be sure to have all hardware equipment for Kellerbus (RS485) available and the according software before switching SDI-12 off.
    There is always only one communication interface active and the hardware of the other interface is switched of meanwhile and
    can only be activated over a software command.