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Hydros CTD-10 Regularly Dropping Out (-9999)

Home Forums Environmental Sensors Hydros CTD-10 Regularly Dropping Out (-9999)

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    • #16440
      James_NZ
      Participant
        Hi all,

        Around 50% of my sites have a problem where the CTD drops out on a regular (not predictable) basis.  This results in -9999 values which may persist for a few readings before returning to nor

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      • #16442
        Shannon Hicks
        Moderator
          We’ve seen that very rarely, usually it happens when the connection between the Mayfly and the sensor is bad, and the fault is either mechanical damage to the sensor cable (rodents chewing, floo
        • #16443
          neilh20
          Participant
            @James ouch.  Looking at the data file, its just the Decagon CTD/SDI-12? readings that are responding -9999 . Typically that means the (SDI-12?) protocol has failed to communicate with the instrument
          • #16445
            James_NZ
            Participant
              Hi @shicks and @neilh20

              I’m leaning more towards an interaction with the MODBUS wing.  I had one station that produced -9999’s constantly when the Turbidity sensor was plugged in, and op

            • #16482
              James_NZ
              Participant

                Hi @shicks.  I’m just wondering if you saw anything in the code above that might be causing this problem?

                Regards,

                James

                 

              • #16483
                Shannon Hicks
                Moderator
                  I’m not familiar with the code regarding the complex loop since it’s not something I’ve ever used, and I’ve also not used one of those modbus wings, so I think Anthony or Neil
                • #16484
                  neilh20
                  Participant
                    @James_NZ – are all your setups the same?.

                    Have you got a spare setup that can be debugged in a local setting? (office with terminal connected)

                    I have a similar setup with an RS485 and SDI-12 on o

                  • #16497
                    James_NZ
                    Participant
                      @shicks, thanks for your help anyway Shannon.   @aufdenkampe, any insight on the code above would be greatly appreciated.


                      @neilh20
                      , yes al

                    • #16498
                      neilh20
                      Participant
                        @james_nz    my process is to stage systems in an accessible context to check the reliability of the systems. This comes from the school of hard knocks working with embedded processors like the Mayf
                      • #16651
                        SGFulton
                        Participant
                          Hi James, we regularly had this problem when using the Decagon CTD-10s connected to a DIY Arduino Mega data logger. We ended up taking the median value of 10 measurements taken 1x/second every 5 mins.
                        • #16666
                          James_NZ
                          Participant

                            @sgfulton  Thank you!

                            I will give this a crack.

                            Regards,

                            James

                             

                             

                          • #16689
                            Sara Damiano
                            Moderator
                              If the communication works sporadically, it’s more likely to be an electrical issue than a code issue.  Coding issues *usually* cause it to not work at all.

                              The -9999 is the library’s va

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