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6 weeks ago I had 24 x Sanyo 240w panels and SMA 4000TL fitted to a S facing roof without shade.
For a few days after, the sun shone very occasionally and at these times I regularly saw over 3kw being generated and peaks of 4.2kW on the screen of the Sunny Boy. Daily yields averaged 13.7kw for the 12 last days in August - none of which were particularly lovely days here in Yorkshire - with a couple of peaks around 21kW and the 3 lowest between 3-5kW.
I returned from holiday yesterday expecting that the recent days of wall to wall sunshine would have made for some record-breaking outputs. It was somewhat surprising to find between 16-17kW was generated each of the fine days. Today the generation pattern is identical and the display on the Sunny Boy at no time has been over 3kW.
Simplisticly it looks as though performance in full sunlight has reduced from 4.2kW to 2.9kW in the space of 6 weeks.
This seems excessive (even allowing for lower angle of the sun) and I'm wondering if something on the inverter has changed. The supply meter was changed 2 weeks ago - it was counting up exported units but that is another battle - so the panels and inverter were isolated / reconnected at that time in the proper manner. Only thing I could think of was whether inverter settings had been modified on commissioning and not saved, meaning they had returned to a default.
Is this reduction of the order to be expected? Maybe someone has knowledge of what a 3.84kWp system has been producing in the past few days. Any thoughts appreciated.
For a few days after, the sun shone very occasionally and at these times I regularly saw over 3kw being generated and peaks of 4.2kW on the screen of the Sunny Boy. Daily yields averaged 13.7kw for the 12 last days in August - none of which were particularly lovely days here in Yorkshire - with a couple of peaks around 21kW and the 3 lowest between 3-5kW.
I returned from holiday yesterday expecting that the recent days of wall to wall sunshine would have made for some record-breaking outputs. It was somewhat surprising to find between 16-17kW was generated each of the fine days. Today the generation pattern is identical and the display on the Sunny Boy at no time has been over 3kW.
Simplisticly it looks as though performance in full sunlight has reduced from 4.2kW to 2.9kW in the space of 6 weeks.
This seems excessive (even allowing for lower angle of the sun) and I'm wondering if something on the inverter has changed. The supply meter was changed 2 weeks ago - it was counting up exported units but that is another battle - so the panels and inverter were isolated / reconnected at that time in the proper manner. Only thing I could think of was whether inverter settings had been modified on commissioning and not saved, meaning they had returned to a default.
Is this reduction of the order to be expected? Maybe someone has knowledge of what a 3.84kWp system has been producing in the past few days. Any thoughts appreciated.
