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Reply To: Negative turbidity readings

Home › Forums › Mayfly Data Logger › Negative turbidity readings › Reply To: Negative turbidity readings

2026-08-14 at 5:48 PM #19783
nick
Participant

    Thank you for the information. I will try the voltmeter for confirmation.

    Can a 7-year-old OBS3+ turb sensor go bad if it has been sitting in a climate-controlled room? It was probably used only a couple of times for testing indoors but has been powered off for at least 6 years. I get a positive reading when exposed in the open air, but when I cover it with a towel, I get a negative reading. I’m getting similar results with two different mayfly logger boards, so I think I can rule out a bad analog-to-digital converter.

    Do you have a recommendation for connecting a OBS3+ turb sensor to the current Multipurpose 6-pin Screw Terminal Grove Adapter?

    I have the white cable (high range signal) going to S2, blue (low range) to S1, red (power) to V+. Since there are only 2 grounds on the current grove adapter, how should I plug in the green, black, and clear wires? Should the black (power ground) go into the V+ slot?

    And just to confirm the OBS3+ jumper is set at 5V in the Auxiliary ADC Grove connector while the ClariVue10 jumper is set at 12V in the Digital pin Grove connector.