Hi all,
I made solar node with RAK4631 module, 5.8dBi antena, small solar panel from solar light and one LiOn battery ( 2599mAh)
Node is on the roof a house in my village.
I tested node without solar panel for two days. Battery voltage has dropped from 4.1V to 3.95V.
With solar panel, battery voltage is still around 4V.
Nicely done Install!
Seeing yours just gave me an idea…
Thinking when I build mine, I’m running the Antenna CoAxial Cable in through the bottom.
This is my 1st solar node. RAK 19007 with a temp/humidity module. No gps. Two 18650s. Two 5v solar panels (from led flood lights) plugged into the USB C and external 8db Helium (thats the claim anyway) dipole and a external WIFI antenna. I’m pleased. Here is a power graph.
This is summer days but I believe I’ll have enough power budget for winter time. My only concern is surviving the monsoon season arriving in July.
I have strict HOA restrictions so it is not on the roof… Yet.
I know you’re excited, but expect failure with the RAK. You need a power supply that puts out 3.7V for the battery connector, 5V for USB, or 0V if those are not possible. If the power supply (batteries) lets the voltage decay, the RAK will crash and stay crashed. The only way to revive it is giving it 5V via USB, obviously impossible when solar powered.
Sorry to throw water on your fire.
I am testing this currently… will try to remember to post the result here. My test with the T-beam (I know, not a good solar node, but just testing) shows that it wakes up when solar power returns… but I am testing the low low solar power scenario still. Message me if I forget to post the results here…
Nice. What is the software? Nice plot. Hope it all works out.
Hi.
I have made similar advancements with solar nodes. However I’m using two 18650 cells in parallel, looking at around 4-5 Ah capacity.
Also, I’m using the RAK green energy buck/boost module to get more flexibility in the input voltages and solar panel selection.
What kind of panel are you using?
I wish to get thru winter, but frankly its not looking too promising as this means 4-6 months of only few hours of direct very low sunlight per day.
However, on my tests, as soon as charging begins, the whole setup powers up even tho if I recall correctly, it has been said that RAK boards will not boot up properly if they have been shut down due to low voltage.
I think I have the RAK green module to thank as its output will only start when input voltage is sufficiently high. This is very promising for remote unattended nodes I would say.
