Which 550w panel do you have?
And do you know if your sunsynk 5kw firmware supports 11a or 13a per string?(Think the spec listed on right hand side or inverter might tell you unless your installer updated your firmware)
My guess would be that your firmware supports the older 11a per string and that you aren't getting your max because the mppt will clip at 11a instead of 13a.
So for example, i pulled the first 550w panel i could find and its rated at 40.99v and 13.42a.
11a firmware will give you 40.99x11=450w per panel so a total of 3150w
13a firmware will give you 40.99x13=532w per panel so a total of 3730w.
I chose smaller 470w jinko panels specifically because they were rated just under 11a vs 500+w panels are usually rated at 13 or more amps which won't hit the panel max on the 5kw sunsynk inverter. The advantage of your bigger sized panels is they will provide more power in less light, but again will never reach their max.
I hit the 6500w(14x470w) inverter max whenever I have clear sunny skies and my load/Battery requires it.
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