Hi there,
i was looking for a solution to monitor multiple room temperature without worrying about batteries and stiil get a wireless installation.
I already have some “ambient light” powered enocean sensors but they are difficult to find on the market and not really cheap when you find them (70+€).
The only cheap alternative i found was this meross thermometer https://www.amazon.it/dp/B0CGLS1BLW but it requires a custom hub and i don’t like integrating it on home assistant via the cloud from meross (i would prefere a “private” integration via mqtt).
I have tested the shelly blu thermometers and they seems to really have a multiple year battery life. So maybe they will be the choice if i can’t find anything “battery free”.
Have you any other ideas about it? Can you suggest something else?
Many people power their “battery” devices with power supply. Just connect the wires to battery connectors and you are good to go…
To substitute 3V battery you can use inexpensive PSU like this: https://aliexpress.com/item/4000299165153.html
Yeah, that’s an idea but i still have to near the thermometer with a usb power supply which is not exactly a clean and easy work to do.
i was curious about why the NodOn solution is not so common…
First reason is price, 50eur is a lot for temp sensor.
Second reason (I assume) is that being solar powered it has to have rechargeable battery inside to be able to work when there is no sunlight. Tiny rechargeable battery has limited cycle life, so probably the battery dies within 4-5 years. At the same time some cheaper non-solar powered sensors offer 2-4years battery life. Better to replace the battery every few years than replace the sensor…
I think that if it was more common it would be cheaper.
But i understand that maybe is not that much of an effort to change batteries ever 3 yrs or so if you have a couple of sensors. It could be challenging if you have to manage dozen of them.
My enocean sensors with a light recharged battery are still working fine even after 4 years aftwer being installed.
But as i said they are pretty expensive.
Hopefully it does another 4 years.
My point was that if you need to replace the battery once every 2-4years, it’s still less hassle than replacing the whole sensor every 4-6years. Independently of quantity.
I didn’t get the point where u say “replacing the whole sensor”. In case the battery fails i can just replace it?
Of course if it is a custom battery it will be problematic but if they use a standard battery it’s not really the whole sensor u need to replace.
Of course if you hare handy, know how to solder and if the whole sensor is not assembled with permanent glue.
Since these sensors are highly optimized for power consumption they likely don’t use voltage regulators and since it can be powered from 3V coin cell, I could imagine that the solar battery is also 3V, maybe Lithium Vanadium Pentoxide type, like those that give power to RTC or computer BIOS.
Just assumption, might be something else…
You mean the optional CR1225 backup battery ?
What about the solar battery?
By the way, EnOcean gives 5yrs battery life in total darkness with that CR1225.
I wonder what’s the whole point of solar here…
Edit:
Battery life for solar on datasheet is only 10days, 0.5% of that coin cell life.
It might use supercapacitor instead of battery.
In that case there’s never need to replace it, and the whole speculation with cycle life is invalid.
So only the price remains. (if you don’t live in Lapland)
One battery change for 10years life vs 2-5x price…
