Working on string configuration adding more panels

[Cabin Rising]

Just picked up 12) 315 watt panels and increasing size of existing solar array. Currently working with a 180 ah 48 volt battery bank with 30 amp charge controller. Using 6) 280 watt panels connecting 3 strings series then parallel. About 80+ voc and 740 watts.

If I can configure the 12) 315 watt panels to work with 30amp charge controller, that is good. If I need to step up to a higher amperage, that will also work.

315 watt panels
voc 45.6
vmp 37.8
lmp 8.45

30 amp charge controller max 160 voc. and 1200 watts. That would make for each string of three panels equaling 135 voc. But 4 strings would be just over the max at 1260 watts. Either going with a 60 amp charge controller or paralleling another 30 amp charge controller in with the existing one.

I hope to double the battery bank next as funds allow. I am using telecom AGM suitcase batteries. Not ideal, but more than plentiful, functional and very inexpensive right now.

Currently the existing array has 4 panels mounted on the south facing roof. Then 2 panels mounted on the west facing roof. There is a drop in output mid afternoon when the sun transitions from south to west facing roof. I hope to rectify this by using 6 panels on both roof sections. This also utilizes late afternoon sun better until it sets.

This also should help during winter when I rely on battery much earlier in the evenings. Hoping to have the battery bank doubled before next winter.

Any corrections, suggestions or advice would be greatly appreciated.

 

[MaikaiLife]

If you have panels in a string where some may have shading or non-direct sunlight it will pull the output of the string down. Two solutions, either isolate the panels further so no one panel in the string has a drop in sunlight, or you can use DC optimizers which will bypass the underperforming panels and increase the string output.

More stings means more mppt inputs/potentially more charge controllers, which might be ideal, otherwise if you’re under the max for your current charge controller with all strings/panels connected, then DC optimizers would maximize the overall array output.