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Reply To: Keller CTD Sensor

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


    A further note on developing a new interface over Modbus; is to then check that when its running the instrument is actually reporting well over that interface.

    I’ve integrated an LT500 Modbus into ModularSensors – and the question now is how well does it perform. Does it actually report and work well. I’ve had this working well on the SDI-12, so I have good confidence it should

    After running it over the weekend  on a two minute reporting, with it sitting in a jar of water “0.21” feet deep – I have some confidence that the Modbus interface is working well.  See attachment


    Its also running with the new Mayfly 1.1 and using the option to SJ27 to monitor the LiPo_V – which is a new feature of the Mayfly 1.1. So while it is doing the Modbus testing,  I’m taking the opportunity to regression test the battery voltage measurement issues.  This is testing the Vbat to measure the LiPo V to 3.8V threshold. The BLUE line is the 10bit Mayfly 1.1 measurement voltage. The GREEN is a reliable 12bit adc source.  The BLUE Vbat is still somewhat noisy jumping around.   I still have an open question as to whether it can be relied on.