Fences and Gates - How strong are fence posts?

Hi, I am planning on installing pool solar panels on a wood rack. The rack measure 246 inches long by 54 inches. It is made up of a 2x4 outer frame with 2x2x51” ribs every two feet. There is ½ inch plywood that covers the surface. The solar panels sit on the ½ inch plywood and when water is flowing thru it, it weight approx 43 lbs. I am thinking of hang the wood rack on my back fence. The wood rack will span over three 4x4 cemented posts. The fence is 75 inches high. I am thinking of hang this wood rack from the top of the fence with hinges as I need to have the wood rack at a 45 degree angle from the fence during the summer months and then hang straight down the fence during the winter months. I plan to add extra legs to support the wood rack when in the 45 degree angle.

My question is will the fence plus the additional legs support this weight??? Or is there a better way??? Is there something else I should be checking???

Any input would be helpful. Thanks

Unless you know how well the fence is built, I would suggest a separate support structure. The fence may need to be repaired or replaced.

The fence seems to be strong and has been standing for 23 years and is still stand straight.