squeakyfrogfarm on Nostr: Here are some photos of the guts of my remote outdoor temperature sensor for my ...
Here are some photos of the guts of my remote outdoor temperature sensor for my #HomeAssistant setup. I will eventually probably expand into a full weather station to measure wind, rain, humidity, etc, but what I really needed this winter was a thermometer to warn me when temps were getting close to freezing so I could check the greenhouses, cover sensitive outdoor plants, etc. The location of our farm is in a natural depression, so on cold, clear nights it can be almost 10 degrees colder than what the local forecasts predict in nearby Austin (and they're wrong about that about half the time, anyway) so I needed to start collecting my own data.
This is an off the shelf cheapo solar light from Amazon. The light function still works, but I usually leave it off and not in "motion detect" mode to preserve battery life. Inside I added a clone of the Wemos D1 mini microcontroller board, wired to the battery through an MCP1700 LDO voltage regulator and a couple of capacitors, with a DS18B20 temperature sensor dangling outside the case through a hole I drilled on the bottom side of the light housing. I sized the hole to be a tight fit for the cable, which sort of causes it to self-seal. No issues with water infiltration yet.
I used the ESPHome plugin for HomeAssistant to program it, set up on a cycle to sleep for 10 minutes and wake for 40 seconds. That gives it just enough time to wake up, connect to wifi (tip: using a static IP address instead of DHCP lets you reduce the wake cycle by a few seconds), and transmit the temperature reading. I tried five minutes between readings, and would run out of battery power overnight, so on this battery, ten minutes is about the minimum.
Not shown in the photo is a strip of thin plastic I cut to fit over the original circuit board that runs the light to keep the D1 board from possibly touching it and causing electrons to go somewhere they're not supposed to go.
Total cost of this setup when I built it six months ago was around $12. Half of that was the solar light, so if you already have some lights, you can add this kind of functionality for about six bucks.
#grownostr #homestead #automation
This is an off the shelf cheapo solar light from Amazon. The light function still works, but I usually leave it off and not in "motion detect" mode to preserve battery life. Inside I added a clone of the Wemos D1 mini microcontroller board, wired to the battery through an MCP1700 LDO voltage regulator and a couple of capacitors, with a DS18B20 temperature sensor dangling outside the case through a hole I drilled on the bottom side of the light housing. I sized the hole to be a tight fit for the cable, which sort of causes it to self-seal. No issues with water infiltration yet.
I used the ESPHome plugin for HomeAssistant to program it, set up on a cycle to sleep for 10 minutes and wake for 40 seconds. That gives it just enough time to wake up, connect to wifi (tip: using a static IP address instead of DHCP lets you reduce the wake cycle by a few seconds), and transmit the temperature reading. I tried five minutes between readings, and would run out of battery power overnight, so on this battery, ten minutes is about the minimum.
Not shown in the photo is a strip of thin plastic I cut to fit over the original circuit board that runs the light to keep the D1 board from possibly touching it and causing electrons to go somewhere they're not supposed to go.
Total cost of this setup when I built it six months ago was around $12. Half of that was the solar light, so if you already have some lights, you can add this kind of functionality for about six bucks.
#grownostr #homestead #automation