I am installing a water depth OEM sensor that is a solid state, continuous fluid level sensor. The sensor provides a resistive output that is inversely proportional to the level of the liquid: the lower the liquid level, the higher the output resistance; the higher the liquid level, the lower the output resistance. We are trying to monitor overland water flow depth during the winter (Ontario). We loomed into using a sonic sensor that does not require to be submerged under water but it does not work because of the small pipe diameters. Pressure transducers do not work since they cannot be frozen or the sensors that can be frozen will not give us a measurement if it is frozen in a little bit of ice. The overland water flow is being measured in-situ on a farm fields where can collect water samples when the over land flow occurs.
The sites we are installing this sensors as well as a couple of other sensors and a data logger that will all run off of a 12v deep cell battery. The data logger I am using can measure voltage + 5v.
My electronics is very rusty since I have not used it for a long time. And the times when I used it was base on a couple of courses along within self training.
- Solid state, continuous fluid level sensor
- Variable resistance: 3000 – 300 ohms + 10%( 3000 at water depth of 1 inch, 300 at water depth of 24 inches)
- Sensor has a reference resistor 3000 + 10% for temperature compensation
- Resolution: < 0.01 inch
I have researched a number of websites and found a lot of information on wheatstone bridges that I can use to convert the resistance to voltage. But since this will be a one arm bridge the voltage output will not be linear. I also found a one arm wheatstone with an op-amp connected to linearize the output, but I do not know type of op-amp and resistances.