Another low cost depth sensor, showing the problems with using “raw sensing”, and the range is very small range 0-10cm and needs recalibrating evertime there is a power cycle. – https://www.vegetronix.com/Products/AquaPlumb/ – but my experiments have shown it has
“Works pretty nicely, except after power off.
Can’t take power off while in water – then reads 0.
Seems as a capacitance based sensor, when powering up needs to baseline the capacitance – guessing on my part – that is needs to be out of the water. Once read a baseline capacitance, then it detects increase in capacitance, water crossing. If the baseline capacitiance could be read, and then programmed, maybe it could survive a power off. “