Recommended C-Band actuator for Solar Tracker

[Lawrence Lile]

I am building a solar tracker. The mechanics are amazingly similar to a C-Band antenna - a pole, an actuator, some electronics, and a big ugly thing that can move around one axis to point at the sky. Only this one receives sun - light, not satel - light. (sorry)



Why the hell would anyone want to build such a thing? Well, why the hell not? Mostly because it is an interesting technical challenge to build from scratch. And a fantastic piece of yard art that makes electricity.

Now, I got an old 8 foot C-Band antenna, but the motor was frozen up, so that didn't work.: I'd like some recommendations on a reliable new actuator motor.

The solar array will be pretty big - 10 foot square. However, the assembly is well balanced. Unlike an antenna, it will not present much unbalanced weight to haul around. It does present a significant surface area for wind to catch like a sail.

Also unlike an antennae, it will move all the time. The electronics will drive it to the east every morning, and then it will track the sun to the west until it sets, then return to the east. So the motor will get a real workout. It will need a 24" actuator to span the angle range it is built for.

I am looking at some 24" actuators on Ebay = Harl 3624 and Powermax PM24. Are either of these any good? I found some threads about quality issues with Harl. What would you recommend for such an application?

 

[Lawrence Lile]

For a picture of a similar machine, google "builditsolar Red Rock Tracker" . The Forum won't let me post the URL for some reason.

 

[toucan-man]

For what it's worth, here's the actuator used by our city.

 

[Lawrence Lile]

Venture Ball Screw. This actuator is 5X as expensive as most of the others I have seen. Is it really that much better? I could spring for this if it is the right tool for the job.

 

[Magic Static]

The actuator will be the most important piece of your project. Don't get cheap!! Look for a quality built unit. The solar tracker will put more use in an actuator than a satellite dish ever does. You will spend $200 or more for a good one. Look at Von Weiss, Venture, Thompson Saginaw brands. This will give you more info to base a decision on.

And ***WELCOME TO THE FORUM****

 

[Lawrence Lile]

So, I note that the Venture ball Screw unit says "40 pulse". Is that referring to a hall sensor output? Can someone link me to some diagrams or technical info on this?

Perhaps I don't need to worry about that at all? The electronics driving the whole mess will get feedback from the sun, not from the motor. Can I just drive this thing with 36VDC, without worrying about these pulses?

 

[FaT Air]

Most likely you won't use the pulses. They are used to precisely aim at a particular point in the sky. The solar trackers just use the sun position. You could, I suppose, design and build a circuit to use the motor voltage in combination with the pulses to have a digital readout of the trackers position. Or a failure detector of some sort that would go off if there are no pulses while the sun moves across the sky. I built the Red Rock simple LED solar tracker circuit and had it drive my BUD across the sky, worked great. Never did make a solar collector though.

 

[T4Runner]

For what it's worth, here's the actuator used by our city.

View attachment 76948View attachment 76949View attachment 76950

Here in California that would last about 24 hrs without barbed wire and concertina wire on top of a chain link fence around it....)

 

[toucan-man]

Here in California that would last about 24 hrs without barbed wire and concertina wire on top of a chain link fence around it....)

The cop shop is next door -- maybe that helps?

 

[i4tas]

For what it's worth, here's the actuator used by our city.

View attachment 76948View attachment 76949View attachment 76950

well in that case the actuator takes 6 months to extend and 6 months to go down, since it is only tracking elevation.

Would love to have a solar power system to power my FTA receivers and TVs, then it would really be a Free (FTA) system, after the upfront costs.

 

[toucan-man]

The panels do track the sun, the photo is not clear about this.

 

[rv1pop]

Would love to have a solar power system to power my FTA receivers and TVs, then it would really be a Free (FTA) system, after the upfront costs.

That is the way it is here! And if you know where to buy, the costs are not that bad! Tracking for me was not a viable option... the cost for the rack and tracking equipment was more than the cost of enough panels to give me the dawn to dark coverage, at $1.50/watt. BTW, inverters waste a lot of power, microHD and 12VDC LED/LCD tv's are the way to go.

It sounds like the OP is using 12 to 20 panels, depending on the brand, and that is 2000 to 4500 watts! I have only 400 watts now, but before winter I need to add 4 more 230 watt panels, which will give me another honest 800 watts.