Need some advice, my system is just a couple of months old. I have Sunsynk 5KW inverter and 6 x JA 390W Mono panels in series.

Panels is facing North on pitch roof. 

The highest production I get is 1.8KW, does this sound correct or could something be wrong? 

Current Volts 264.7V

I am currently maxing out on about 80% of my installed capacity. Actual numbers will depend on variables, such as the roof pitch (my pitch is quite steep). Also some days are just better than others. 

Not too shabby for winter season

Thanks, thought it was normal just wanted to confirm.