i NEED HELP FIGURING WIRE SIZE FOR 9ea - 24V 255W IN SERIES 625 FT TO POWER HOUSE COP-ALU. E

MY PANELS ARE UP 500 FT UP A STEEP MOUNTAIN SIDE. i GOING WITH SERIES TO GET A HIGHER VOLTAGE BECAUSE OF THE DISTANCE IT NEEDS TO GO. THESE PANELS WILL ONLY HAVE TWO SETTING FOR THE SUN TO HIT FOR POWER.THEY ARE CANADIAN MADE. THEY WILL SIT ON TOP OF 12 FT POLES 3 PANELS PER POLE. ONE COLLECTOR BOX FUSED UP BY THE PANELS ANOTHER FUSE BOX/ DISCONNECT AT THE POWER HOUSE. YOU CANNOT WALK UP THE MOUNTAINSIDE IT IS TO STEEP BUT THERE IS A ROPE TO HELP YOU GET UP. NO TRAILS NO ROADS NEAR. THE WIRE WILL BE IN 2IN CONDUIT ONLY PARTLY BURIED BECAUSE OF THE ROCK. i HAVE A 24V SYSTEM AT THE HOUSE MAGNUM INVERTOR 3924, OUTBACK 60 CONTROLLER, 800 AH BANK 1 1/2 HR OF SUNLIGHT FROM MID NOVEMBER TO FERBRUARY