For my four recently constructed one-watt solar LoRa mesh repeaters, I tested the solar charging. This told me that there was something wrong with one of the four repeaters.
By now I have learned is that with a newly constructed solar LoRa mesh repeater, it is unwise is to deploy it right away, especially if the repeater is placed at a location that is remote or difficult to reach. I learned this the hard way, with my first few solar LoRa mesh repeaters. I would deploy a repeater on a mountain, and I would then see its battery run down, and then it would cease to function. I would then have to hike up the mountain to replace the repeater.
Recently I constructed four solar-powered one-watt repeaters (blog article), and then I tested the repeaters to see if they charge properly. Each repeater provides telemetry (seen at right) including its core temperature and state-of-charge, which I logged over a period of days. The graph above shows the results.
You can see from the graph that for three of the repeaters (1W1, 1W2, and 1W3) the battery state dropped at night (at points 3 and 5) and rose up to full charge the next day (at points 4 and 6). This told me they were charging properly.
But you can also see that for repeater 1W4 (the green line with triangles pointing “up”) there was no charging going on. The line was monotonic downward.
So opened up the repeater to see what was wrong. It turns out that back when I assembled this repeater, I had failed to plug in the PH1.5 cable all the way. So the solar panel was not connected electrically to this circuit board.
I plugged in the cable. Now I will repeat my testing of the solar repeater.
Leave a Reply