Shelly H T Gen3 Ivory Wi-Fi and Bluetooth Smart Temperature Humidity Sensor with Remote App Control Monitoring Smart

I am a software developer. I spent a lot of time reviewing different devices, interfaces and their specifications. I wrote software to manage this device, including RPC, Bluetooth and MQTT. I am also very experienced in the dynamics of environmental monitoring for residential and commercial buildings. In my opinion this is an excellent humidity and temperature monitor at a low cost for home automation. The interfaces are well documented, easy to work with and there are numerous open-source implementations and libraries available. If you are a non-developer or a home automation user, this device will monitor humidity and temperature and perform well. I have read comments regarding long times to report changes. Temperature and humidity do not change rapidly in normal residential or commercial environments. If you require fast change detection, you are designing for a problem this device is not intended for. This device reports on wakeup every six minutes. The reason is to save battery life. That is sufficient in normal environments. If you require fast response times, select a different type of device that is plugged into a power source and reports continuously. The device will need to support rapid temperature and humidity changes and those types of instruments are much more expensive. The big issue is accuracy when detecting changes. It does no good to use a cheap device that reports every 5 seconds if the changes are only +-20% accurate. Accuracy requires either time or money. Read more

I have tried several wi-fi temperature sensors to monitor the temperature(and humidity) in my house while I away for several months. This is by far the best of the lot. The others I tried(TempCube and Govee) always failed in one way or another. They would lose power and when they got power restored, would be basically dead to me : they would not reconnect to my internet at home, so there was no way for me to get data sent to my phone from the device. This Shelly H&T has not failed me yet - when power was lost in my town back at home and it came back on, the H&T Gen3 reconnected and started sending me data right away. Highly recommended and not very expensive. Don't want to sound like an advertisement, but, forget the rest this is by far the best. Read more

Pretty accurate hygrometer with great e-paper (e-ink?) display. Display is large enough to read everything clearly without my glasses and set up was fairly easy. Bought this unit because of the flexibility to take batteries for power or use USB cable to power the unit as we didn’t want to replace or recharge batteries frequently, in addition to good display. Knocked off 1 star because USB cable needs to be removed every time the back cover needs to be removed to sync. Sync/reset button is under the battery cover, and the cover cannot be removed without unplugging USB cable. (Only required during initial setup) Shouldn’t be a problem for those who choose batteries. Specifically bought this unit to hook it up with Home Assistant with Shelly plugin and it did not disappoint. Picked it up fine and reading well over WiFi. The price of this unit is about the same as other WiFi Hygrometers on the market, but can be expensive if we wanted this throughout the house. But for the reliability so far of Shelly products, we’d definitely consider this unit again. Read more

I had great hope for this device. On paper it looked perfect for my use case and I purchased six units. I returned all six after two units failed to operate on battery and a third was intermittent on battery. I did not have time to debug the problem. With that said, registering the device is not clean and simple, and I was able to mess it up, but once configured one unit seemed to work well. Note, to conserve battery power, these devices report temp and humidity once, then power down WiFi and wait for the temp or humidity to change before powering up WiFi and reporting the new values. So if temp or humidity change a lot, then battery life will be shorter. The ePaper display is a great idea if you need to directly see the measured temp and humidity vs checking the app. The app allows you to bias the measured temp and humidity readings, so you can sync the units to one another or another thermostat. This is a useful feature to compensate for normal variations between devices. Again, the device looked good on paper, but the battery issue was killer for me. Read more

I have three of these. I just have them hit a local web server and report temperature and humidity. If you want something to poll, this isn't what you are looking for. They instead only connect to wifi and "push" data when the temperature or humidity changes. I suspect thats due to it running on AA batteries, and trying to get good battery life. As long as you are okay with that, then these work great. I'm using one to check outdoor temperature, and one to monitor the temperature of my dog house. I have the web server kick on a local power switch when it gets too cold, which kicks on a 200w panel heater (designed for chickens) and warms the dog house. Then I have it kick off when it gets too hot. The dog appreciates it when its super cold out. I have it kick on at 55 and off at 65. I wouldn't want to use it for too narrow of a temperature range though because I've seen it wait until 53 to turn on and it sometimes stays on a few degrees higher then 65. I prefer Shelley devices since they can be used without cloud involvement and they are good for hobbyists that find no reason to send sensor data all the way to a data center just so local devices can then reach back out to the data center to act upon the data. When you have everything working locally, response times are in the millisecond range instead of the second range (which can grow to the minutes range during high usage). Read more