Teyleten Robot PH Value Data Detection and Acquisition Sensor Module Acidity and Alkalinity Sensor Monitoring and Control ph0-14 for Arduino

Got it setup and reading data using a few tutorials. Needed to have a software calibration value before tuning more finely with the potentiometer.Ph Model seems tight. I can get it to be accurate on the high end or on the low end but not both. If I dial in the high PH then the low gets inaccurate.I will order this product again because I only need it accurate on the high side. don't need the full range of measurement. (could also be my calibration mixes)Doesn't come with calibration fluid.I will probably make a video of this on my YouTube channel 'Random Projects with Sam'

Very difficult to calibrate even with a known good pH meter the readings are all over the place.The op amp circuit is poorly designed and one can’t adjust the offset voltage below 2.66 on my unit.Will never work at 3.3 and barely works at 5 volts.Single ended approach does not work well when a pH probe outputs a differential voltage above and below a pH value of 7 at approximately +/- 59mV/ per 1 pH increment and this probe is good to 0.5 pH step according to data sheet so 29.5mV per .5 pH increments. Do not buy this unless your willing to spend a lot of time on the bench and fine tuning the math in your code. I recommend using a voltage divider on the output of your using 3.3 volt and especially for ESP32 where the ADC only accept up-to 1.0-1.2 Volts max full scale resolution otherwise you’ll never get it working.Good luck and buyer beware..Mike S.

Maybe ok for range experiments or for beginners but look somewhere else for precise readings.

Teach me right for not testing the probe when I got it. A month later I got around to actually working with this and low and behold it doesn't work! Following several different guides still resulted in no change in the analog value. It didn't matter if it was lemon juice or distilled water it always read the same. Sure the potentiometer change it a bit but the liquid didn't change anything.

I was unable to make the needed potentiometer adjustments to set the output to 2.5v for a PH of 7. Further, once i was able to adjust this with an additional potentiometer for a consistent reading on ph 7, i found that the readings would fluctuate (+- 2ph) at higher and lower ph's.Giving 2 stars for the great price but if you are measuring anything mildly important and don't have the time or technical ability to account for the errors in calibration, there are better but only slightly more expensive options.

This is a C-minus device, that doesn't work well enough for a simple fish tank sensor.

OneWire scans as [], voltage is constant at 3.3V from PH pin using ADC. no matter what liquid is used. They were tested with standard PH solutions with PH at 4, 7, and 10.

pH readings not accurate