Was: Re: RFX dying??? Now: Pond Level

[Dave Fleck]

Hi Jerry,

I have a MPXV4006GP air pressure sensor, which was designed to measure water depth in washing machines. It’s attached to a thin plastic tube that runs from my controller to the bottom of the pond. There’s also a temperature probe next to it to measure the water temperature.  The controller is an ESP8266 at the pond that sends back the measurements (along with the controller temperature, soil moisture, temperature of the pump housing, and a microphone attached to the pump that was part of a failed attempt to detect when the pond ran dry by sensing the pump cavitating). Because of PV=NRT, the pressure of the air in the tube needs to be corrected for temperature, so I use the water temperature and air temperature from my Tempest station to correct the level. It is far from perfect. I often have to adjust the threshold for filling throughout the year because the temperature compensation isn’t exact, plus there’s an ever so small amount of air leaks out over time allowing the tube to gradually fill with water. I had to take a ton of data and do regressions to come up with the formula I have, but I need to do more. Or perhaps some AI.

Dave

> On Apr 4, 2021, at 5:24 PM, Jerry — MacSolutions <jerry at stlmacguy.com> wrote:
> 
> Dave,
> 
> Might I ask what you’re using to measure the level of your pond?
> 
> —Jerry
> 
>> On Apr 4, 2021, at 4:21 PM, Dave Fleck <dfleck at pacifier.com <mailto:dfleck at pacifier.com>> wrote:
>> 
>> 3/22/21 4:26:28 AM.5816 Received value for Pond Level of 4996. (json) 
> 
> _______________________________________________
> XTensionList mailing list
> XTensionList at machomeautomation.com
> http://mail.machomeautomation.com/mailman/listinfo/xtensionlist

----------
"Hell, there are no rules here-- we're trying to accomplish something." -- Thomas A. Edison

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.machomeautomation.com/pipermail/xtensionlist/attachments/20210404/276a211e/attachment.html>