New to openhab, I will start with a very simple thing, a smart wifi socket powering a water pump with a rule to turn it on every day for 10 minutes.
I am slightly paranoid though and am thinking what would happen if for whatever reason the socket does not turn off, especially if I am not at home. The result would be flooding and burned out pump or worse.
I am not entirely sure what to search for on google but I would need some kind of dump preferrably analog switch that just cuts off power from the time the power kicks in plus N minutes. Or cut off power after certain power usage limit is reached. I guess I could get one of those daily/weekly timer sockets but I would need to match the timing with my rules which is too much work.
I’m grateful if someone can point me in the right direction and tell me what would be a good solution for this, preferrably something prebuilt and ready to use.
I think your paranoia is justified. It’s very easy to have switches turn off after a period of time in OH, but if your switch loses its WiFi connection then you’re out of luck. Your insurance might not cover water damage from leaving a pump on.
Belkin Wemo plugs store their rules locally, so they’ll work without an Internet connection. However, I don’t know if you can turn one on with openHAB and then have it automatically turn itself off.
I don’t usually recommend Wemos, because I found them to be very frustrating in my five years of using them. It’s been awhile, though, so maybe they’ve improved.
You could also get a water sensor to place next to the pump to warn you if there’s ever a flood.
Just to clarify, the pump runs the grass watering sprinklers so there wouldn’t be any flood outside per-se (other than huge water waste), but once the source is emptied the pump would run dry which would lead to disaster.
I will need openhab more in the future because I plan to add selenoid valves to divert into different sections which will require all rules to be centrally controlled. So a flaky connection or sprinklers not working one day is not really the problem, just needs an insurance that it turns off so you can go to bed or leave home with good conciense.
@rossko75 I searched for that but did not find anything meaningful. Can you link me to a specific product to continue from there?
Stairwell/staircase timer. The ancestral type is a large pushbutton fitted on each communal stairwell landing in an apartment block… Slapping the button turns on the light and initiates a clockwork gizmo to turn it off again in a few minutes. As you slog up the building, you slap each button along the way,
These days of course there are electronic versions, random example
which can be connected to a number of pushbuttons.
For control by openHAB, you’d use something with a relay output to simulate a pushbutton. The something can be zwave, wifi, whatever wired technology you are using, who cares.
openHAB just makes a second or two pulse on the relay to begin a preset N minute cycle. It’s pretty failsafe.
Of course you can have a real test/manual pushbutton as well as the remote/simulated one.
As @rpwong says, some gadgets like Wemo or I am sure some Sonoff include timed outputs, much easier to use but slightly less self-contained in the disaster proofing.
Thanks, I found the exact term I am looking for: “off delay relay”. One that pings itself on power on, like this: https://www.qualitymobilevideo.com/tdr12v2.html just a version that can do 15min periods or so.
