June 17, 20214 yr Hi, I have 5 strings of 3 330W Panels connected to my Mecer. YES - I know I am nearing 5kW PV, but have done so for a reason. See, my MPPT/PV amps never exceed 60A, although the sticker says 80A PV. Is it a print fault perhaps? Then, if it IS only 60A, can I get a replacement MPPT card that is 80A perhaps? Thanks, Gert
June 18, 20214 yr 21 hours ago, Gert-Claassen said: See, my MPPT/PV amps never exceed 60A, although the sticker says 80A PV. Is it a print fault perhaps? If your panels are 72-cell (330 W is about the transition between 60-cell and 72-cell), then the solar charge controller may be limiting power due to high PV voltage. What PV voltage are you seeing? If it's over about 134 V, you will be limited to ~75% of rated output, which would be 60 battery amps. If that's the case, the solution is to re-wire for 2P. Sadly, because you have an odd number of panels, that means getting an extra panel, or not using one of them. But you may get more power from 2S7P than 3S5P, and your SCC may well last longer. 21 hours ago, Gert-Claassen said: Then, if it IS only 60A, can I get a replacement MPPT card that is 80A perhaps? Unless your machine was made before about 2017, it will have an 80 A MPPT. I don't think you can easily obtain a replacement MPPT card.
June 18, 20214 yr Author Hi, OK, so my panels are 3 x 330 in series, and then 5 of those strings in parallel. VOC sits at 125V DC, and inverter sticker says 145 MAX, so I think I am within bounds? Gert
June 19, 20214 yr 8 hours ago, Gert-Claassen said: VOC sits at 125V DC, OK, and since it's nearly the middle of winter, you should be OK with that voltage. 8 hours ago, Gert-Claassen said: inverter sticker says 145 MAX That's the absolute maximum, never exceed voltage. You get zero power through at 145 V. 8 hours ago, Gert-Claassen said: I think I am within bounds? Yes. Close, but OK. You don't need to rewire 2S. I don't know why you're getting a maximum of 60 A, unless setting 2 (maximum charge current) is set to that value, or solar balance is disabled (setting 31). Some have reported that the SCC runs hotter with 3S than 2S; can you see the temperature reported by the inverter on your monitoring software? Excessive temperature could reduce solar charging output. Edited June 19, 20214 yr by Coulomb Added last sentence.
June 19, 20214 yr Author Hi, My setting 2 is set to 140A, BUT my 31 was disabled. I have now enabled it and will check what influence it has today. Inverter temp runs between 35 and 40 degrees, depending on load - never seen the temp go up with just charging though. Will let you know - thanks for your response. Gert
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