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Reply To: Reading -9999 on all Sensors

Home Forums Mayfly Data Logger Reading -9999 on all Sensors Reply To: Reading -9999 on all Sensors

#18756
Shannon Hicks
Moderator

    Have you tried measuring the voltage being applied to the sensors by using a voltmeter when the channel scanning sketch is running?  For the turbidity sensor’s screw terminal board, put the voltmeter’s red probe on either of the V+ screws, and the black probe on either of the GND screws.  For the CTD sensor’s 3.5mm headphone jack adapter board put the probes on the two points shown in the attached photo.