Well, after my post on making my
solar trackers over here, it seems only fair to describe the problems (and cure) that came soon after.
We'd had weeks of continuous rain. The ground and everything in, on and around it, was soaking. Then we had a storm. Substantial wind gusts, but also very very turbulent - blowing from one direction, then in a moment it'd be blowing from a completely different direction. It did this for hours! Trees were pushed over all over the state.
Well, next sunny day the panels outputs were "odd". Something I couldn't put my finger on, so I went topside to have a look.
Then I came back and got my camera.
Looking down, you can see the great gaping hole around the concrete. These things were set in 3' deep, 12" diameter concrete. The soaked ground, followed by the buffeting wind had worked all the arrays loose in the ground and just spun them around like kids toys!
These two are actually "pointing" to the same place - north. At least, they THINK they are!
I considered a variety of remedies. None particularly appealed. In the end, I decided it had to be a dual effort. I had to try to stop the ground getting quite so wet, and I had to stop the thing flopping around in the hole. The panels had suffered no damage. The frame, tracking mechanism, head, actuator and even the post itself were all in perfect condition. No damage. It was purely that it was moving in the ground.
So... once the ground had dried out enough to work on, I cleared an area around the post, squared everything back up. Cut some diagonal struts to spread the load. Put some mesh in the hole and welded it to the legs. I also cleaned out around the hole, rammed it full of dirt, hard.
Then, mixed up concrete. Don't let this fool you. There's the equivalent of 8 bags of concrete in there!
The second one just did not want to come straight. I ended up needing my hand winch to pull it upright. I had to drive a 1.5" diameter steel spike 4 feet into the ground to hold it. Even then, the ground was still soft enough I pulled the spike sideways 6".
It got the same treatment.
My welding is utter crap. My excuse was that it was hot, I was working cramped, and it was galvanised steel!
Still, I did all 4 faces of each, I doubt they will fall off.
The last one. It was getting easier now. I thought.
The cat was so impressed, he decided to bring me a snack.