LoRA BME280 Environmental Node (with webbased backend)

Hi Stefan,

i use this nodes for about three months now without any drop in voltage. So i think they will work a little bit longer :wink: I also removed the power LED and the voltage regulator.

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Hi BjoernA,

could you please state which battery you are using and what is your time interval (T) for data transmission?



i’am using these cheap 3.6V lithium batterys.
My transmission interval is 10 minutes.

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It’s been a while that I posted something of a status update in this topic, but here it comes.

Last week I followed a Angular 5 course for my work and one thing we had to do was to work out and implement a case. Well what better way to do that then to rebuild my webbased backed :slight_smile:

There are still some small things to do (CSS just isn’t my thing) but the base is there and it’s LIVE :


After some code cleanup I will post the sources on my github page.

Note : the old backend is still live at https://ssl.bolkesteijn.nl:8943/env/


first google to the rescue ANGULAR :wink:

What’s these CH2i BME 280 sensors :joy::joy:

I wouldn’t know :wink:

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Finally all parts had arrived, i have build a test setup on a breadboard and measured the power consumption. It uses round about 50mA while sending and 27,3μA in deep sleep. A battery calculator says that the battery (ER14505) should run 5 years :sunglasses:.
Next step design and print a case and than installing it.

By the way, i use Cayenne LPP to visualize the data, if you wish i can make a pull request to add my changes to your code. It is implemented via #ifdef statements so it can be easily changed between Cayenne and your data format by setting a #define.

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Give it a pull :slight_smile:

This thread has made me very happy :slight_smile:

I’ve been working with Pro Mini, RFM95 and BME280 to build a low-power monitoring node. I can get it all working OK< but I’m struggling with the LP side of it. This looks exactly like what I’m after - and I also use Cayenne at the back end, so I’ll be keeping a close eye on you as well @biermi !

I’m literally in the middle of adding a lux and UV sensor - the code’s easy enough, designing a case which is small and contains all the electronics is a little trickier, but I’m getting there.


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the original BME280 library has changed, so be careful loading the whole content from lex_ph2lb

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which one is that ? :wink:

Are the SMD resistors needed if I do not want the Button and LED? All I am trying to do is have the ProMini, RFM95W and the BME.

If you look at the schematic

  • No button and led - can remove all red parts
  • No Microchip DEVEUI chip, then you can remove blue parts
  • Depending on your BME280 sensor breakout board, may be you don’t need black parts. these are I2C pullup and some breakout board already have them, just check if BME280 is seen without them with an I2C scan sketch, if not place them/
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I have made and printed a small case for indoor usage.



@Charles @lex_ph2lb

You need to do conformal coating on PCBs which are exposed to high humidity / low temp.
Please see this link

Electrolube HPA200H High Performance Acrylic Conformal Coating


Bookmarked. Thanks for the tip.

Do you have any photos of your boards exposed to water / humidity outside after a year or so?
Just curious.
I have left several boards without a coat outside. Within three weeks there was a corrosion on pins and a lot of oxidation

Not at the moment. But I can do that and will take a few this evening.

The worst one was one which I hung above a galvanized plate. Those connectors where with 2 months corroded. Replaced them with first quality material (the orignal was china export) and didn’t have any problems after that.

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