Hi,
I bought a couple of used panels this weekend, the rated VOC is 38V. Yesterday in full sun they only got to 29V (obviously open circuit, no load). When I put a load on them, the 250W panels peaked at 140W (using mppt grid tie inverter as load). I'm thinking the panels are bad, would you agree?
When I buy panels in the future, would you expect the VOC to be close to the rated value even on a cloudy day or would you need direct sunlight to achieve this? Are there fractions of the VOC that when missing indicate particular faults, ie, bad diode, dead cells?
Many thanks
I bought a couple of used panels this weekend, the rated VOC is 38V. Yesterday in full sun they only got to 29V (obviously open circuit, no load). When I put a load on them, the 250W panels peaked at 140W (using mppt grid tie inverter as load). I'm thinking the panels are bad, would you agree?
When I buy panels in the future, would you expect the VOC to be close to the rated value even on a cloudy day or would you need direct sunlight to achieve this? Are there fractions of the VOC that when missing indicate particular faults, ie, bad diode, dead cells?
Many thanks