Hi. I’m interested to know if there is a way for a OSPi hacker to deal, programatically, with the state (open/closed) of a DIY switch. That is:
Where would the relevant pins be.
USE CASE: I find a way to detect if the pressure in my irrigation system AFTER the valve has fallen below a preset limit- thus indicating a likely broken-off sprinkler head or damaged pipe. I would then program the OSPi to email me a notification of same.
I have in mind a detector that opens or closes a circuit. If, after the sprinkler has been on for 15 seconds or so, the switch is in non-normal state (eg open when it should be closed) the system would send me a notification. I’d then go a test the sprinklers.
You ought to be able to use any of the unused pins (see the user manual) for your pressure sensor. You could then have software running on the Pi independent of OpenSprinkler that would monitor the pressure. If the pressure dropped to low, you could interact with OpenSprinkler via the API to stop the program. Your software could also notify you through whatever means you want it to.
Thanks Mike. Apart from my ideas for a DIY pressure sensor, do you know of any inexpensive (under $10) commercial pressure sensors that will flip a switch when the circuit pressure goes above or below a preset amount?
While not under $10 i did find this which might be what I would use https://www.amazon.com/dp/B00RCPDCQU it’s $18. It’s analog so you’ll need to also have an ADC somewhere between the sensor and your Pi. you could use an Arduino or an esp8266 for that it you’ve got one. I don’t think you need a separate switch – just turn the irrigation valve off through the API. I don’t recall if it supports it but you might even be able to disable the zone through the API to prevent the program from opening the valve back up the next time it is scheduled to run.