Over voltage & amps
My solar array is 2 strings of 8 panels ( 8x300w ) . So 2 strings 2400w ea. VOC per string is 300VDC or 600VDC per system. This is Max for the SMA Rapid Shut Down box. I thought with a DC drop in wiring ( 60' ) I would never reach that point. I was wrong and the RS box now shuts off ( high noon ) one string ( B ) when this happens. To re-boot the RS the system will turn off at night and have both A & B channels on in the morning. So like Tony I need to drop a little DC (from my array). Adding 50' more of PV line might do it but since I have two 160W panels, I might replace the 2 panels (300W) on the end of each string with the 160W panels. This is mixing panels but since this is a series system I thought I might get some advice PRO or CON. The Building Permit will need to be changed and they might not like it ( or not ).
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