Comments (2)
Hey @ericu65,
This is both interesting and intriguing, and I can't say I've experienced a similar issue yet. Specially seeing the battery voltage going up! Given you confirmed the odd behavior with a multimeter (in-circuit I'm assuming), one wild idea is that it could be related to ambient temperature. I'm not super convinced, because the temp variation would have to be kinda large.
For example, check out this chart from a CR2032 datasheet:
There is a correlation between temp and voltage reading, which could explain the first graph if in your test you used colder tap water, for example -- but I would expect the voltage to slowly go back up as the temp settles back. Or it could explain the second chart (voltage going up) if you moved the sensor indoor from outside.
Do you recall doing any of these?
A couple of other (relatively far fetched) ideas:
- Temporary partial short caused by water around the battery clip or some exposed pads
- There is a known "initial drift" see wiki in the moisture reading in new sensors, though I haven't seen it affecting the battery reading
from b-parasite.
Hi @rbaron
Thanks for looking into it. I think this rules out a known change in the way the voltage ADC pin is read. That was my main concern, either a change from version to version, or a misconfigured build, which seems to not be the case. Out of the 5 these two have given me the most trouble regarding excessive battery usage often needing to change them every 2 months so it's likely something electrical that would explain these swings I see here too. Seems to be pretty stable now and I've put them in soil.
To your good points:
- temperature change would surely explain this but not the case here, have been inside in the same place the whole time and the room's temperature changes do not correlate to the voltage changes (see above - obsessive data collection is real), and the water wasn't replaced as far as I can remember - and the SHTC3 doesn't show any big swings either;
- voltage was measured in-circuit but not under TX load;
- I've also seen the drift for moisture reading but only in soil, not in water - though not for voltage until now;
- an intermittent low resistance short either at the pins or at the battery clip is most likely the real reason as per the previous experience with these two boards.
Notice the calibration referencing VCC working beautifully with no change to moisture during the voltage swings - really nicely done:
Since there's nothing to be fixed I will close this shortly.
Thank you
from b-parasite.
Related Issues (20)
- Wiki instructions for docker build are outdated HOT 6
- Firmware flashing problem "Failed to attach to CPU" HOT 2
- Zigbee code does not update value HOT 10
- Low battery voltage HOT 4
- Idea - move moisture sensing to the back side of the PCB
- Additional component file for 2 side printing and E73-2G4M08S1CX HOT 13
- Device not found when scanning BLE HOT 4
- Multible Sensors with on MCU HOT 5
- Idea: add piezo speaker to aid plant-sitting HOT 10
- Idea: a 'light' version without the sensor itself? HOT 3
- Questions from a novice HOT 1
- Adding HOT 1
- Adding PAR-capable light sensor to the board? HOT 1
- Q4 orientation question from JLCPCD (I've read related docs and issues) HOT 2
- How to read raw data with soil_read_loop sample? HOT 2
- Identify BLE device HOT 3
- Bogus illuminance and moisture readings HOT 5
- Repeating measurement HOT 6
- Not an issue - Integration of b-parasite with LTE(nrf9160 and nrf52840)
Recommend Projects
-
React
A declarative, efficient, and flexible JavaScript library for building user interfaces.
-
Vue.js
🖖 Vue.js is a progressive, incrementally-adoptable JavaScript framework for building UI on the web.
-
Typescript
TypeScript is a superset of JavaScript that compiles to clean JavaScript output.
-
TensorFlow
An Open Source Machine Learning Framework for Everyone
-
Django
The Web framework for perfectionists with deadlines.
-
Laravel
A PHP framework for web artisans
-
D3
Bring data to life with SVG, Canvas and HTML. 📊📈🎉
-
Recommend Topics
-
javascript
JavaScript (JS) is a lightweight interpreted programming language with first-class functions.
-
web
Some thing interesting about web. New door for the world.
-
server
A server is a program made to process requests and deliver data to clients.
-
Machine learning
Machine learning is a way of modeling and interpreting data that allows a piece of software to respond intelligently.
-
Visualization
Some thing interesting about visualization, use data art
-
Game
Some thing interesting about game, make everyone happy.
Recommend Org
-
Facebook
We are working to build community through open source technology. NB: members must have two-factor auth.
-
Microsoft
Open source projects and samples from Microsoft.
-
Google
Google ❤️ Open Source for everyone.
-
Alibaba
Alibaba Open Source for everyone
-
D3
Data-Driven Documents codes.
-
Tencent
China tencent open source team.
from b-parasite.