printbarron
New Member
A friend of our was grappling with whether or not to replace her 2kW grid tie system. She didn't want to see it go in the landfill. I told we would take it, as any PV system was better than what we had (which was nothing). A local retired installer told me to test the voltage of all panels. At the time I didn't know I should also test the amperage. The panels are Sharp 165W and the inverter, a Sunny Boy 3000 (2019).
I finished mounting and connecting our 12 used panels and got everything approved by our power cooperative. The lineman tested our output and it was very low, only 0.8A AC at the time. Indeed, the inverter also shows very low wattage produced, though that number doesn’t align with the amps AC. At 0.8A X 240VAC, I would expect to see ~192W output reading from the inverter(?).
The inverter shows ~42-108 W on a sunny morning – about 5% of what the system “should" be. I was expecting at least 50-60% of what it would have been new. I’ve tested every panel as another installer has instructed, and aside from one dud, all look fairly consistent (see diagram below).
Even if one string is low (string A), does it make sense that the total output watts would be compromised by one string (the inverter accepts two separate strings)? I might try swapping two higher watt panels from string A, with two low panels from string B to see if anything improves. In your experience is there another thing I should be checking? The inverter seems happy, with no errors, but I know nothing beyond what the readout is showing.
Any help is appreciated!
(Thinking about swapping poor for decent, to bolster string B, making string A all poor performers.)
I finished mounting and connecting our 12 used panels and got everything approved by our power cooperative. The lineman tested our output and it was very low, only 0.8A AC at the time. Indeed, the inverter also shows very low wattage produced, though that number doesn’t align with the amps AC. At 0.8A X 240VAC, I would expect to see ~192W output reading from the inverter(?).
The inverter shows ~42-108 W on a sunny morning – about 5% of what the system “should" be. I was expecting at least 50-60% of what it would have been new. I’ve tested every panel as another installer has instructed, and aside from one dud, all look fairly consistent (see diagram below).
Even if one string is low (string A), does it make sense that the total output watts would be compromised by one string (the inverter accepts two separate strings)? I might try swapping two higher watt panels from string A, with two low panels from string B to see if anything improves. In your experience is there another thing I should be checking? The inverter seems happy, with no errors, but I know nothing beyond what the readout is showing.
Any help is appreciated!
(Thinking about swapping poor for decent, to bolster string B, making string A all poor performers.)
