I think the battery level is not well calibrated with these sensors.
For sure none seem to start @ 100% (due to being factory fitted I suppose)
also some people see rapid drops then no change for a while.
Followup on results of the shower test.
I moved one of the sensors into my bathroom, had a shower, and put it back into another room afterward.
It looks like some of the results were as close together as 3 minutes, and indeed results are reported when a significant change in temperature was recorded.
I also checked humidity, which shows the spike in humidity, a total of 5 recorded results in space between 23:22 and 23:42.
Results Temperature:
Results Humidity:
Lastly, @hijinx, on the other sensor, unmoved since yesterday to today the reading was 43% at about 16:50, and is now 41% today at approx 17:10. At this rate it would be a few weeks or months at most, I think.
Is this sensor reporting granular enough for your automation?
Also re battery level, most of my Xiaomi batteries are in the 40% to 55% range.
They are all about 6 months or so old.
- I don’t think that the batteries start at or ever report 100%
- I don’t think they report drain linearly
- I expect that the device will stop working before it’s battery gets to 0%
- I’m pretty sure that you cannot accurately compare between devices
Bottom line they are a rough guide only.
Yeah, that sounds about right, the batteries should hopefully last a while.
I’ve had my Xiaomi sensors for only a couple weeks now.
As for the granularity for the heating automation, I’m not sure entirely so I think I’ll just need to try it and see after the weather cools down some more…
At the moment, nothing changes, it’s too warm.
The reactive reports due to changes is encouraging though, as at the moment I have the heating automation report from an Aeotec ZW100 MultiSensor 6, which is manually configured to report in at strict 10 minute intervals.
I guess that if the Xiaomi sensor can react in less than 10 minutes then that would be a win? 
My xiaomi sensor number state didn’t update occasionally, last update is 2 hours ago, it can’t be normal. But it is ok with xiaomi’s app.
The temperature+humidity sensor reports with changes over 6% change on humidiy or 0.5 degrees on temperature. This seemed good enough for me, for my heating system, but in the real life, it has some problems for example:
Let’s say you have your heating desired temperature set to 21º, and the last temperature reported by the sensor is 20.9, so the heater is on. Then, at a particular moment in time due to the current climate conditions, it takes 5 minutes to increase 0.1 degree, so to reach 20 degrees, it only takes 5 minutes, but to reach 21.4 that is the point where the sensor senses a 0.5 change and emits a new value, it takes 25 minutes. So there’s an extra 20 minutes of heating that could be avoided just if the sensor could be polled every 5 minutes.
I’m pretty disgusted with this, as there’s no easy way to get around this, and this situation happens more often than i would. So if anyone know a way to hack the electronics or the gateway to increase the interval it would be nice. I prefer to change the batteries more often that having this bad behaviour.
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I’m considering making HA control my heating and have exactly the same concerns on using the xiaomi sensors. Any news?
Add force_update to your config.
Hi, @sjee can you elaborate where that force_update setting goes?
I can see no reference to it in the Xiaomi docs.
It is not xiaomi specific but a setting which can be used to update a state even if it did not change.
Hi, thanks for the link and info, but I’m not denying that this is a valid option.
I’m still not sure where advise that the option be added?
on the gateway config?
on the thermostat config?
somewhere in customize for a device?
That does not fetch new data from the sensor.
That is a visual issue only (and I don’t think the complaint on that thread is an issue). Your suggestion does not request new values from the hardware, it only “updates” the entity with the same old value.
No I have not tried it, but I’m pretty sure it won’t do anything.
I just made a suggestion… tried it myself and doesn’t work. It looks like I get even less values in the In the mi app as in HA for some reason.
I use the Temp / Humidity sensors all over the house, especially in the bath / shower rooms, where if they humidity hits a certain value it turns on a sonoff switch that operates the extractor fan.
Im not sure what the update frequency is, but its mins not hours, actually quite responsive.
Could you still tell where to add the force_update setting?
I really don’t think the force_update feature would work for this device. I had Xiaomi temp sensors hooked up to SmartThings before getting the native hub and the behavior was exactly the same with no way to manually setup an interval. The sensors themselves don’t send their state to the gateway unless there is a significant change (I think 1/2 degree was mentioned). You can’t force the hub to update information it’s not receiving from the device. I think the only way to change this would be if someone cracked the firmware and we were able to upload our own remix.
I’m simply amazed at how many times I’ve asked a straightforward question but it cannot be answered.
It’s a community driven project. There is no full time support team but just users helping other users. I’m sorry to hear you have different expectations.
I think there is enough explanation in this topic already why force_update will not work.