Using my Twine to tell me when to water a plant
This is a multipart question...
A.) If I stick the moisture sensor into the moist dirt in a potted plant, it reads "wet." I'm just curious how dry it will need to be for it to read "dry." This sensor seems very sensitive. Just holding it in my hand reads "wet." I'm guessing anything that conducts electricity is going to cause it to read "wet," right? So will dry dirt still read "wet" because it probably still conducts electricity a tiny bit? Or is that not how it works?
B.) Will leaving the sensor tip in damp soil for an extended period of time (days, months, decades) be bad for it? Do I need to worry about it corroding or anything like that?
Thanks in advance for any advice!
And thanks to Supermechanical guys for making this awesome gizmo.
So yes, it does work.
But I am still curious about whether or not I should be worried about corrosion, or rust, or anything like that. I'm thinking of attaching some leads to the sensor so that if it does cause corrosion, it will just be on some replaceable wires, and not the sensor itself. What do you guys think?
my plant is dying and my twine still says its wet. :-(
Looks like this sensor should probably not be used for plant monitoring.
This idea also solves my problem of using my Twine on my Winter holiday problem; needing to alert someone in town while I am away somewhere where it is warm; if one or both of two things happen; the level in my sump rises beyond where the sump pump should kick in, and/or the temperature in my house somewhere near the thermostat location goes below some safe temperature, and there is perhaps 30 feet between the thermostat and the sump, and I have a 4 foot sensor cable.
One more problem with this, however, if the sump pump failure and furnace failure are due to a long-time power failure, none of this will work. Which is why we need a "sign-of-life" trigger from the Twine server if our Twine has not reported in (because the WiFi has gone down) for some time, eg. at 1 hour, again at 2 hours, etc., which would tell someone that they need to go check for power at the house.
Don't worry about the prongs corroding - that's why we used gold. (Also makes a great pendant.)
A "network up/down" virtual sensor would be a great addition. It's on the to-do list.
EDIT: Just added this as a feature request, As it would be useful in other situations too.