6kW Rooftop Solar Wire sizing Required

Hi Guys,

I am planning to contract a 6kW system. Going to use 24*250Wp panels, 5.4 kW inverter, along with 4 in 1 out DC Junction box through 6 sqmm string cables.
3 Strings, 8 panels connected in series.

Is it enough to have 10A fuse at the input side of DC JB and 40 A on the output side of DC JB ?

I would like to know how to size wire further after DC Junction box and how to size the AC Distribution box (eq: 2 pole MCCB) ?



  • tampasolar
    tampasolar Registered Users Posts: 65 ✭✭
    There is no panel string that isnt within spec with #10. Recently some Lowes stores have clearanced their 'off-color' spools of #10. Those stores are smaller and dont want to stock brown,yellow or orange #10 anymore. Like$35 instead of $95 per 500 foot roll.
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