hello. i have 4 solar panels series producing 120volt dc.i want a schematic with they go under 105v to start a power supply.
is there an easy way to do this?
is there an easy way to do this?
If you use a contactor rated at 24volts DC and a 1N5377BG Zener diode, when the voltage reaches approximately 15Volts plus the diode breakdown voltage (in this case 91v), the contactor will drop out connecting and the contacts will change for a power supply instead of the solar panels.
it have 4x250watt.they were parallel until now and was producing 5kwh/day,almost all my house.but now i want to add two more because the winter is coming and the current would be huge so i changed to series connection.
p.s.i tried a 30v relay with 91v zener and it seems to work.i will do more testing tomorrow.
p.s.i tried a 30v relay with 91v zener and it seems to work.i will do more testing tomorrow.
Won't the panel voltage rise once the load is disconnected, causing the relay to behave like a buzzer? Maybe it's better to just isolate the panels with a rectifier. You can spare a diode drop, and DC will be prone to arcing if you don't use the right kind of contactor or some kind of semiconductor switch.
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Yes. To avoid this effect in my regulator, I used a window comparator: starts charging at 20V and stops at 14V at the regulator's input.
it didn't work.when the inverter disconnected the full voltage passed through the relay and the zener and the soldering melt.
i guess i need a comparator.
i guess i need a comparator.
Remember that solar cells are current sources, not voltage. then it's output impedance is high.
The equivalent model is escentially a current source in // to a diode join.
The equivalent model is escentially a current source in // to a diode join.
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