Atom Lite with Earth sensor powered by Tailbat
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Hello all,
I'm playing with Atom Lite and Earth sensor for measuring of soil resistance.
I'm coding it in micropython as of right now. My idea was to power Atom L. with tailbat and create multiple instances of it for each flower. It should send data few times a day (x 4-6) to MQTT via wifi. But it seems that tailbat can power Atom L. only for short time period (few hours max) :(Are there any best practices how to achieve best ratio of power consumption ? e.g. some deep sleep ?
Thx
BR -
Hello @findmyname
the Atom TailBat uses an IP5303 which according to its datasheet turns off automatically after 32s if the load is less than 45 mA. From what I can tell this 'feature' cannot be disabled.
Google translated from IP5303 datasheet:
Automatic load detection time | TloadD | The load current is continuously less than 45mA | 32sSo in order to keep the Atom TailBat from shutting off, the M5Atom needs to consume at least 45mA. With the 190mAh battery that only gives about 4 hours.
ESP32 deep sleep (or light sleep) only works as long as ESP32 is powered. And while the sleep modes would conserve energy (longer battery life) they at the same time will not keep the Atom TailBat from shutting off (too little current).
One way (untested) I could see is to put the ESP32 into deep sleep for less than 32 seconds, then briefly wake up (and consume more than 45 mA) to re-trigger the 32 seconds timeout in IP5303, then go back to sleep.
Thanks
Felix -
Hello again
ok, I've tried out my proposed solution using an M5Atom Lite with a M5Power C Hat (which is similar to the M5Atom TailBat as it turns off if the load is below 45 mA).
When the M5Atom Lite is running it consumes about 50 to 90 mA which keeps the power on as it is above the cutoff current of 45 mA.
When the M5Atom Lite is in deep sleep it consumes about 11 mA which doesn't keep the power on, but waking up M5Atom Lite every 30 seconds from deep sleep solves that.
However with the M5Atom TailBat battery of 190mAh that still only gives about 17 hours of operation.
Thanks
Felix -
Hi @Felix ,
First of all thanks for amazing write up.
Automatic load detection time | TloadD | The load current is continuously less than 45mA | 32s
Oh no that is a bad news for me :) this is kind of important info - I would expect that this is mentioned on m5stack page.
However with the M5Atom TailBat battery of 190mAh that still only gives about 17 hours of operation.
Really nice test thanks. What is your procedure to measure power consumption?
Do you know what is appropriate HW to power on Atom L. for weeks, months on battery ?
Thx
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Hello @findmyname
you are welcome.
You can find a link in my signature which also explains the tool I am using to measure power consumption.
Well, if you insist on using an M5Atom the only option I see is to use a large enough battery to cover the desired timespan.
If, however, you are open to different hardware you can find boards which are designed specifically for low power consumption. (I don't want to place a direct link here, but if you search for something like
esp32 guide low poweryou should be able to find some helpful info.)Thanks
Felix -
@felmue said in Atom Lite with Earth sensor powered by Tailbat:
If, however, you are open to different hardware you can find boards which are designed specifically for low power consumption.
I chose Atom Lite with Tail Bat because of:
- Out of box solution e.g. board with battery including case.
- It is small and it looks nice.
- Cheap / good price.
- Bunch of sensors which can be easily connected.
I don't know about any other HW which fits these categories. I'm using also other products for home automation which can be on battery for 2 years at least but it is x3 more expensive so I'm kind of surprised with the result :(
