Tasmota temperature sensors

I've been doing a little home automation with Home Assistant recently and this involved putting temperature sensors in every room. I started out with some ugly stripboard SHT11 based things but they were unreliable and inaccurate.

During a Banggood sale I managed to pick up some Wemos 'shields' with an SHT30 temperature/humidity sensor so I converted all my sensors over to these. Tidier but still a bare circuit board with power LEDs lighting the room at night.

I fiddled around in OpenSCAD and came up with a fairly decent 3D printed enclosure and now have eight sensors dotted around my house, including the shed. This design leaves the SHT30 sticking out in free air with a 'baffle' to separate it from the rest of the device. Even so the temperature readings are massively effected by heat soak from the ESP8266 and quite inefficient LDO on the board. I've now put this on Thingiverse.

To fix the heat soak you need to connect D0 to RST on the D1 mini with a short piece of wire and enable deep sleep so they draw (and waste) much less power. In Tasmota this needs two console commands...

TelePeriod 10
DeepSleepTime 300

...the 'TelePeriod' means it sends data 10s after connecting to WiFi and 'DeepSleepTime' means it sleeps until the next five minute interval on the clock. If you're copying this example don't issue the commands until you're happy with the Tasmota configuration. The short wake time makes it a pain to issue changes later.

Now they send decent sensor readings, reliably.

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