Hi Jeff22,
I am using 2 (ea.) 10 ft. extension cables + 13 ft. (included with Solar Panel) for a total length of 33 ft. I haven’t tried any farther, but you could try it. The cable only costs $4.55 a piece, so if you do try it, you aren’t out much money!
But, I don’t recommend it though. You are extending this quite a long distance and there are many limitations/variables when extending low voltage long distances (attenuation/loss in cable, voltage drop problems, resistance in cable, placement of solar panel, etc.)
I am not saying it “will” or “won’t” work. But for the cost of the cable, you could give it a shot! You won’t be out much money and if it doesn’t work and you can always use the cables on other Ring DC products with the same connector type!
Hope this helps!