i finally decided to start tinkering with home automation and i want to use openHAB. I have a server, network etc setup, but i need some help choosing the first items for the automation-part
I need a relais and a temperature sensor. They stay outside, so they should be able to deal with temperatures from -25°C to +60°C (or something along those lines). They wont sit in the pouring rain, but i cant guarentee absolute dryness or a certain humidity. Finally they should use some kind of wireless connection that works with openHAB and is very reliable (the life of 4 turtles is on the line!).
Do you have any suggestions on what technology, brand or model i should use here? I searched the board, and will continuing to do so, but i dont think that i can pick out the best device for my requirements for myself.
You’ll need to specify range here to narrow the field. 10m, 100m, through walls ? Also power options - battery, or is mains available at sensor location? What load does the relay have to control - a battery powered LED, or a high power heater?
The range depends on where they are attached to the ethernet, i guess. The shortest would be 25m, almost a direct line, with 2 “walls” (1x stone and 1x some kind of greenhouse). If i have the wireless receiver near my server its more like 40m with 4 walls, kinda hard to get a signal through. I guess i will place the receiver as best as i can.
I have mains avaiable and it would be great if no device would run on battery, since batteries and very low temperatures (winter) arent a perfect matchup in my experience.
The controlled load is about 100w (at 230v, reptile warming bulb). The bulb comes with a controlling device that should guarantee a softstart, i never tested if that works though.
Sounds like a job for a Sonoff, a WiFi mains control relay with options for temp and humidity sensing. You need a little technical skill to modify one for local control rather than via chinese cloud
The Sonoff devices have an operating temperature of 0-40°C, if those datasheets are correct. The Sonoff devices i found so far seem to be indoor devices, if i am not mistaken …?
Yep. Obviously you can put them in an enclosure.
I wouldn’t expect low-temperature operation to be an issue in practice, the device is powered off mains and will self-warm to an extent.
It’s more likely to mess up at high temperatures, there aren’t many pieces of non-military grade electronic kit verified to work at 60C
If this is all a worry, it might be time to rethink it as a wired solution, all control and switchgear indoors and just a pair of wires to a remote temperature sensor.
Yeah maybe you are right. I will look deeper into those Sonoffs now, but it seems i need a bit of equipment to flash the firmware. Thank you for the tipp though
I’d not expect any problems outdoor, as long as you protect the Sonoff from rain and high humidity. All further details (including setup instructions) should be described here: