μniversal fire

EC-Salinity Probe

Measure Electrical Conductivity in Siemens, Total Dissolved Solids in PPM, and Salinity in PSU and PPT. Monitor hydroponic nutrient levels or salinity in aquariums, pools, and soil.

  • Electrical Conductivity in Siemens
  • Total Dissolved Solids in PPM
  • Salinity in PSU and PPT

ECSalinity probe

Available on Tindie
or make one with the source code and schematics

What it is

An ATTiny85 programmed as an I2C slave, a DS18B20 waterproof temperature probe, and a two-electrode EC probe. It measures conductance and converts it into a temperature-compensated SI derived unit called a Siemens. From that value, it determines TDS and salinity.

Using it

A library is provided to make using the probe easy and there is extensive documentation on the use and setup of the device. The library is available for download and installation in the Arduino Library Manager, PlatformIO Library Manager, and Particle.io IDE. There are also python implementations for Raspberry Pi and MicroPython.

C++:
#include <ECSalinity.h>
EC_Salinity ec;

mS = ec.measureEC();
Python:
from ecsalinity import ecsalinity
ec = ecsalinity(3)

mS = ec.measureEC()

Probe Selection

Any 2-electrode probe can be attached to the device, but it is recommended to only use the probes provided by uFire. They are designed to be inexpensive and replaceable after approximately six months to a year of light use. The probe can be kept submerged.


Support and Questions

If you have any questions, find a bug, or have any suggestions, go to this project’s GitHub page and submit an Issue or Pull Request. Or you can send an email to questions@ufire.co.