DIY EC sensor

[Ranjib]

Yes, I believe both ADS1015 and ADS1115 are very reliable in this regard. They are much slower (~1kHz compared to 200-500 kHz for microcontrollers) but more accurate. The ADS1015 has 12 bits, e.g. about 1mV resolution in the largest range, and only about 1-2mV error, whereas the Pico has up to 8mV in certain places and the ESP32 has 140mV.

I have read that the ESP32‘s problem mainly arises in the full range, so if one uses a lower range and simply steps down the voltage oneself with a few resistors, this could become much better and can replace an ADS1015 for our purposes I guess.

That is awesome to know. i would always prefer an esp32 based solution , because it’s comparatively cheaper and simpler to build over ads115 . As long as it fits the reef keeping use cases, we are gold

 

[alex12eqw]

Hi Sral,
when searching for a cheap ec measurement alternative i just came across your thread. It sounds very cool and reliable. I am wondering if you have somewhere uploaded the final ciruit, so that i can build it myself. I am not really into electronics therefore it would help me alot:)

 

[Sral]

Phew, I haven't gone beyond a breadboard until now and haven't worked on this version for a long time. I could probably create a design that's simple enough and publish the code. At least some day, when I can find the time :loudly-crying-face:

I was working on a ready-to-buy version that's currently in the final polishing phases.

 

[Sral]

Alright, the ready-to-buy version seems to be up and running at robo-tank.ca
Though rob is currently unobtainium on R2R ^^

I'll work on getting some info on here and publish to Github.

 

[Sral]

Okay, looking back here now and then.

Seems like I never put any concrete circuit diagram on here to show the two versions that I have settled on. That will be the next step.