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Makerfabs / Lora-Soil-Moisture-Sensor

Lora Soil Moisture Sensor
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ADC: sensorValue #5

Open i4things opened 2 years ago

i4things commented 2 years ago

Any table that based on the sensor value to get the soil moisture in % ?

littlejogi commented 2 years ago

i use mprocent =(1-((moisture-560) / 324 ))*100;

I don't know how accurate this value is. For me it looks ok

i4things commented 2 years ago

I use : mpercent = 100 - ((moisture - 500) / 4) e.g. 500 = 100% i - 900 = 0%

but after some experiments - it looks like a better calculation should use the battery voltage also - as the battery voltage is used as a reference voltage and when the battery goes down the min/max values are changing

e.g. battery ADC result with moisture ADC result

bat - 1023 -> moist ( 527(in water -100%) - 894 (in air - 0%) ) bat - 920 -> moist ( 508 - 880 )

e.g. I was hoping someone before me t have done some more detailed experiments :)