💬 Homini In-Wall Battery Powered Light Switch Module
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@Samuel235 Ah ok. Well its basically for everyone here who has build a coincell based mysensor node. How long can you run them?
@LastSamurai, There are a few links on the build page here for information regarding battery powering found here. Have a look at the link in the "Need to know more?" Section just before the buying guide section on that page. Some very useful information regarding this topic :)
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@Samuel235 said:
Are you asking about this module itself on a coincell or are you asking about @Nca78's solution while running on a coincell?
Sorry, I don't really get your question ;) What do you mean with "this module"? I was talking about a atmega + nrf + some sensor run by a coincell, (in general, but in this case how @Nca78 did it).
@LastSamurai said:
@Samuel235 said:
Are you asking about this module itself on a coincell or are you asking about @Nca78's solution while running on a coincell?
Sorry, I don't really get your question ;) What do you mean with "this module"? I was talking about a atmega + nrf + some sensor run by a coincell, (in general, but in this case how @Nca78 did it).
I did a door sensor to test running on a coincell (CR2032), nothing very advanced: I use the standard script for switch with sleep, with a CHANGE interupt to get the node out of sleep. I just added some code to lower frequency at 1MHz (didn't even do it with the bootloader, I will do that next time). I measure voltage of the battery by comparing with internal voltage reference every open+close cycle (and send it only if it changed of course), and at the moment after around one month of usage I don't notice any significative change in battery level, it's fluctuating between measurements but always in the same range.
In sleep mode and door closed consuption is around 2uA, when door is opened I have a "big" loss of current through the reed switch, it's around 60uA (tried many values of resistors and never got a better consumption than this). Fortunately the door is closed way more than it's opened, so with the sending of status changes I expect the CR2032 to last around one year. -
@LastSamurai said:
@Samuel235 said:
Are you asking about this module itself on a coincell or are you asking about @Nca78's solution while running on a coincell?
Sorry, I don't really get your question ;) What do you mean with "this module"? I was talking about a atmega + nrf + some sensor run by a coincell, (in general, but in this case how @Nca78 did it).
I did a door sensor to test running on a coincell (CR2032), nothing very advanced: I use the standard script for switch with sleep, with a CHANGE interupt to get the node out of sleep. I just added some code to lower frequency at 1MHz (didn't even do it with the bootloader, I will do that next time). I measure voltage of the battery by comparing with internal voltage reference every open+close cycle (and send it only if it changed of course), and at the moment after around one month of usage I don't notice any significative change in battery level, it's fluctuating between measurements but always in the same range.
In sleep mode and door closed consuption is around 2uA, when door is opened I have a "big" loss of current through the reed switch, it's around 60uA (tried many values of resistors and never got a better consumption than this). Fortunately the door is closed way more than it's opened, so with the sending of status changes I expect the CR2032 to last around one year. -
in deep sleep ;)
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Nice project!
A typical CR2032 ( I checked the Energizer datasheet) has a self discharge of 1% / year and a capacity of 240mAh, so that's a self discharge rate of about 2.4mA/year, or about 6.6uA per day. The ATmega328P at 3V in full power down with watchdog disabled has a supply current of about 0.6uAh (datasheet page 603). That equates to 14.4uA/day or twice the self discharge of the coin cell. Still excellent and I suppose the coin cell might last a few years if you keep the size and frequency of the transmitted packets low :) -
@TheGuv, I'm hoping Rev3 will bring in power sensing and more interrupt enabled switches.
This is at the back of my list at the moment as it works, just not 100% optimized right now. I have a couple of modules in the pipeline for release very soon now, once they're out and stable i will be optimizing this to become a better solution. Keep yourself posted to my updates if you're interest ;)
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@Samuel235, I hve a much simpler question, What kind of switch are you using? A standaard light switch, did you make a custom one? Could you add a picture?
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@Samuel235, I hve a much simpler question, What kind of switch are you using? A standaard light switch, did you make a custom one? Could you add a picture?
@JahFyahh About half way through the forum topic regarding this module has this image: https://forum.mysensors.org/uploads/files/1455483350043-image.jpeg
A little unclear but you can see the faceplate of the switch. Its a normal wall mount light switch.
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@Samuel235 Sorry I must have overlooked it, the post has grown. It looks good, AliExpress? Did you ever get the chance to look at those RF switches?
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@Samuel235 Sorry I must have overlooked it, the post has grown. It looks good, AliExpress? Did you ever get the chance to look at those RF switches?
