I’m a newbee with regards to home automation but I’m liking it. I stumbled into this Smart Home stuff because of a home project I did to improve the efficiency of the heating convector in our living room. I’ve “supercharged” it with 9 140mm PWM PC case fans. The steering of the fans is done by a small Chinese module with a temperature probe. This probe is attached in the convector pit. On the module you can set a temperature at which the fans start spinning faster. The hotter the temperature measured, the faster the fans turn. But when the temperature threshold isn’t reached, the fans turn at 10% of their max speed. So the fans always rotate. Which seems a waste.
We have Tado thermostats and I was hoping that I could use the Tado integration in Home Assistant to trigger a power plug as soon as Tado requests heating in the living room. But since polling to Tado is done with a delay of 5 minutes this trigger isn’t useful.
What device could I use to generate a realtime trigger so that I can power up my fans.
Or am I overlooking possibilities with Tado?
Thank you already for your inputs.
I’m not familiar with Tado device, so can can speak to increasing it’s sampling rate. Also not sure what temperature ranges you are working with. With those said, I and others have been successful with a number of the bluetooth sensor devices to get near realtime data at sampiling rates in the order of 10’s of samples per minute. Link below is a bit of analysis I did of a couple different BLE sensors. Search the forum for BLE temperature, Govee and Xiaomi LYWSD03MMC-ATC to find several different solutions. For example, I use a Govee BLE unit to monitor stove hood temperatures to see if they are above kitchen room temperature, if so I alert that stove has been left on.
Hi David,
Thank you very much for your answer.
I’ll certainly look into BLE sensors. The reason why you’re suggesting BLE sensors instead of Zigbee sensors is because of the higher polling ratios?
Best regards
Sven
Yes, I went down a rabbit hole with exploring some of these temperature, humidity and pressure sensors. Have a read of post linked below I recently did…
Yes, so far all the Zigbee devices I have tried have slower broadcast and sampling rates than the bluetooth devices.
The only way I know to control the sampling rate of the sensors it is build your own unit using a ESP, Arduino or similar as others on this thread have suggested or purchase a far more expensive off the shelf ‘pro’ device. The USD 4 Xiaomi LYWSD03MMC ATC MI bluetooth devices with the custom firmware installed allow changing the broadcast rate of reading, but I am not sure if they have yet figured out how to change the sensor sampling rates. That said for the price, the temperature reading seem to update several times a minute and are pretty accurate, the humidity reading update at a lower rate and are slightly less accurate. But overall they are my favorite low cost device.
I bought some from AliExpress and another set for from Banggood both at same time and about same price. The Banggood units arrived in about 10 day and the AliExpress in 20 days, this was back in November.
I will be interested to hear of your experience. I have been very pleased. I found the same posts about how to get the custom firmware on the units.
There are a number of people who have taken this work even further, it’s pretty amazing the smart folks out there.
I used this guys firmware and stopped there, I have yet to have a need for anything more:
I hope you are able to flash the firmware on the units without any problem, I was able to. Deciding on the ‘receiving’ hardware and software is a bit more of some work. I started trying to use Home Assistant, python natively on my raspberry pi. But I could not make that work reliably. Others have had good success there, and I think the python software on the Raspberry Pi has improved considerably since I tried it.
It’s been a week or two since I have received the Xiaomi Thermometers. Flashing with the custom firmwares went smoothly.
I must say that integration with Home Assistant through the BLE monitor (GitHub - custom-components/ble_monitor: Passively monitors BLE messages from Xiaomi Mijia BLE MiBeacon, Qingping, ATC, Xiaomi Scale and Kegtron sensors) works nicely. I’m using the built-in Bluetooth from my RPi. I had to change the location of my RPi to the living room to get a better BT connection. For testing purposes OK, but I can’t leave the RPi in the living room. (conflicting interests with my wife ) So I’m now looking for some sort of external Bluetooth receiver.
Although the Xiaomi sensors will be a perfect fit for situations where you want to track/monitor temperature and humidity it is in fact still a little bit too slow for my purpose. (But I’ve built my automation with it nonetheless. )
There seem to be two delays: 1) is obviously the interval at which the sensor reports to HA and 2) is the delay at which the sensor registers temperature change.
Of course I realize that it is merely an environmental sensor and not a probe which would detect temperature fluctuations (near) real-time. Logically a probe will probably be more energy consuming, I assume. And this makes it hard to find in a low power (battery) solution, I guess.
But as said the Xiaomi sensors are definitely not a lost “investment” (10€ for 3 sensors) .
Hello! Thanks for the update. Glad the Xiaomi’s are working. As I said, earlier in this thread, I struggled with the python bluetooth stuff. Same core code that the HA component uses. That was when I moved away from python and coded a c program that talks at a very low level with the Bluetooth stack on linux. I do run it on a separate RPI from my HA server, but it can run on a HA RPI as long as it is the only thing using bluetooth. That said, you can put multiple BLE USB adapters in a RPI and the program I wrote can use any of them. I think got three BLE adapter running at once on a RPI as a test.
When you say ‘slow’, what kind of time frame are you talking? I have not seen any delay in the reading from any of my BLE sensors, I have 20 of the running around the house. I get about 400 records from each sensor per hour.
If you have a couple of hours, you might try compiling the program on the RPI and see how it performs for you. It does talk via MQTT, so you need to have a MQTT server running to get the data into HA.
) So I’m now looking for some sort of external Bluetooth receiver.
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