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Reply To: PH Sensor Issue

Home Forums Environmental Sensors PH Sensor Issue Reply To: PH Sensor Issue

#12973
Shannon Hicks
Keymaster

What pin is the sensor getting power from? If it’s the Switched 5v pin (labeled SW5), or from one of the grove terminals (assuming you’ve moved the jumper over to the 5v setting), you still need to switch on the 5V boost regulator by putting this line, preferably in your setup routine:

digitalWrite(22, HIGH);

The 5v boost regulator (as well as the switched 3.3v aux regulator) are not enabled unless you set pin 22 high. This is so the regulators don’t stay on all the time and waste power when the logger is sleeping between measurements. If you want to leave it on constantly, it’s easiest to put the statement above in your setup routine. If you’re making a sleeping logger, then you’ll want to set 22 high and low at different times in your loop, making sure to add sufficient time for the sensor to settle after powering up before taking a reading.