series pv panels into parallel in combiner box

hi,

what voltage is the battery bank?

 what charge controller are you using?

what is the distance from the combiner to the charge controller?

with those answers I can try to help more

cheers,
james
altE staff

for optimum operation, since all the modules you mentioned are 18v nominal, 3 in series would work out best.  If it were my system, I would not add two modules, I would add another series string of three.  since you already have the sharp modules, I would make sure they were either 208, 216 or 224 variants that are the closest to what you have now for best mppt performance.   

because you controller is an mppt, it can down convert the voltage from 54 nominal to 48 nominal for you.  the issue is that in finding the maximum power point, the modules and the string sizes need to be the same.

your controller can handle 5 stings of 3 in series before it is maxed out.  since your batteries are at 48v, i am afraid that two in series may not provide sufficient voltage for charging on warmer summer days when vmp is driven down, that is why 3 in series is recommended.

cheers,

james
altE staff

thank you much, Jim