Post by lbendlin on Dec 12, 2018 7:17:28 GMT -8
I seem to get into a pattern with my Suncontrol board, and I don't like it.
Let's assume the battery powers my setup successfully through the night, with about 35% capacity left at sunrise. Temperatures are below freezing. Thermistor is connected to the board and sitting next to the battery.
As soon as the solar panels catch the first sun the solar input light and the charging light (red and yellow) come on. Shortly thereafter the green light comes on as well, and the USB output gets cut off. I can only get it to switch on again by unplugging the solar cells from the board and then cycling the output switch.
It's as if the board tries to start charging and then realizes it's too cold to charge, and instead of just stopping the charging it shuts the output down as well.
My expectation would be that the output would stay on as long as the battery voltage is above the threshold (seems to be 3.43V for my case) regardless of what the charging circuitry is up to. (The attached chart mentions "capacity" - I define 4.10V as 100%, and 3.43V as 0%. Crude, but works for me. "Contribution" is the amount of wattage supplied by the solar panel compared to the wattage consumed by the load)
Two solar panels in parallel, with 10 1W zener diodes 6.2V across the leads (to be replaced by a single 10W diode).
Same issue when using only one panel.
Would be happy to get suggestions on how to avoid that morning shutdown if possible.
Let's assume the battery powers my setup successfully through the night, with about 35% capacity left at sunrise. Temperatures are below freezing. Thermistor is connected to the board and sitting next to the battery.
As soon as the solar panels catch the first sun the solar input light and the charging light (red and yellow) come on. Shortly thereafter the green light comes on as well, and the USB output gets cut off. I can only get it to switch on again by unplugging the solar cells from the board and then cycling the output switch.
It's as if the board tries to start charging and then realizes it's too cold to charge, and instead of just stopping the charging it shuts the output down as well.
My expectation would be that the output would stay on as long as the battery voltage is above the threshold (seems to be 3.43V for my case) regardless of what the charging circuitry is up to. (The attached chart mentions "capacity" - I define 4.10V as 100%, and 3.43V as 0%. Crude, but works for me. "Contribution" is the amount of wattage supplied by the solar panel compared to the wattage consumed by the load)
Two solar panels in parallel, with 10 1W zener diodes 6.2V across the leads (to be replaced by a single 10W diode).
Same issue when using only one panel.
Would be happy to get suggestions on how to avoid that morning shutdown if possible.
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