System:
3kW Stackable 48V 150VDC 80A Off-Grid Inverter by Growatt
Used Axitec AC-410MH/144V Panels (quantity 4)
48V 100AH LiFePower4 Battery by EG4 (Does not matter for this question, but including it anyway)
I have a small off-grid cabin and am building my first system. I thought all my research was going great, but am having a problem with the configuration of my panels to fit into the VOC limitations of my Growatt inverter. The Growatt inverter requires a minimum of 80 VOC to charge the battery, with a max allowed VOC of 145 VOC. With the panels I purchased, my original plan was to have two runs of 2 panels, since the panels have a stated vmpp of 42.3 volts and a VOC of 50.4 volts. After testing the panels for the last few weeks, I am only averaging about 30-40 volts per panel. This means that my original plan will not provide enough constant voltage to consistently charge the battery, but it I run all 4 in series, the peak voltage will be higher that the max allowed VOC for the Growatt inverter.
The easy fix would be to use 3 panels in series, and not use the 4th, but I would really like to use the power from all 4.
Now here comes my noob question: Can I run a series of 3, and then use a combiner box or Y connector to connect the one remaining panel? Are there any other configurations that would work that I am not seeing? My Growatt only has one solar input, and I really do not want to buy another small inverter for the one panel if I do not have to (though that is an option I guess). I could also buy 2 additional panels to even out the strings, but I bought my current panels used, so not sure I could find more (at least locally).
3kW Stackable 48V 150VDC 80A Off-Grid Inverter by Growatt
Used Axitec AC-410MH/144V Panels (quantity 4)
48V 100AH LiFePower4 Battery by EG4 (Does not matter for this question, but including it anyway)
I have a small off-grid cabin and am building my first system. I thought all my research was going great, but am having a problem with the configuration of my panels to fit into the VOC limitations of my Growatt inverter. The Growatt inverter requires a minimum of 80 VOC to charge the battery, with a max allowed VOC of 145 VOC. With the panels I purchased, my original plan was to have two runs of 2 panels, since the panels have a stated vmpp of 42.3 volts and a VOC of 50.4 volts. After testing the panels for the last few weeks, I am only averaging about 30-40 volts per panel. This means that my original plan will not provide enough constant voltage to consistently charge the battery, but it I run all 4 in series, the peak voltage will be higher that the max allowed VOC for the Growatt inverter.
The easy fix would be to use 3 panels in series, and not use the 4th, but I would really like to use the power from all 4.
Now here comes my noob question: Can I run a series of 3, and then use a combiner box or Y connector to connect the one remaining panel? Are there any other configurations that would work that I am not seeing? My Growatt only has one solar input, and I really do not want to buy another small inverter for the one panel if I do not have to (though that is an option I guess). I could also buy 2 additional panels to even out the strings, but I bought my current panels used, so not sure I could find more (at least locally).
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