Solar Tracker Circuit

If you cannot get your tracker circuit to work, you might be able to modify it to work based on this circuit diagram:

http://www.projectfreepower.com/

I'm not an EE by any stretch of the imagination, but I did build this circuit and it works very well.....cheap to build too!

Try it, you'll like it!

That looks a lot simpler... simple is good. Especially when it comes to fault finding if you are not an experienced with electronics.

Mind it looks like it only rotates one way, which would need slip rings unless I'm missing something?
Del

It is way overcomplicated. And I am an EE. You need 2 solar cell element or photodiode separated by a vertical shade. The whole assembly better not be precise at all. If it works once every 5-10 degrees, it is fine. Anything finer is asking for trouble. Within 10 degrees the collector produces essentially the same power. The driver for the motor is a H drive, bipolar, nothing special. It works as is then. But, if you want to avoid hunting (moving back and forth) you may want to add a smith trigger type of hysteresis between the sensor and the H drive. But, at first I would not bother with it.

Reply to #6. If the cat, er contextman knows what I am talking about, he can build it. Otherwise he can ask somebody to do so. And yes, Virginia, there is such a circuit as a Schmitt trigger. It is the intentional introduction of hysteresis, preventing hunting type oscillation. It will cost him 2 or 4 resistors to generate the necessary positive feedback, to make it happen.

Before I would accept the mechanical complication of moving the cells around to track the sun, I would use the money to buy another cell system and place (northern hemisphere) one looking SE and one looking SW.

Easy to build a strong support and who cares how hard the wind blows and NOTHING mechanical to go wrong.....

By the way, does your original circuit have the sensors shaded correctly?

AAAAAaaaaaaarrrrrrrrggggghhhh!!

Using my tracker:-

When the sun shines on the panel it drives the collector to a position where it's back in the shade.

You need a photovoltaic panel

http://www.mindsetsonline.co.uk/product_info.php?cPath=16_445&products_id=312

£3.90 4.4V 90 mA

A solar motor:-

http://www.mindsetsonline.co.uk/product_info.php?cPath=16_13_437&products_id=191

https://www.mindsetsonline.co.uk/images/sml_solar.pdf

£1.50 1.5 to 4.5V

And a gear box

http://www.mindsetsonline.co.uk/product_info.php?cPath=16_13_436&products_id=199

£4.06 Plus £0.92 for the 40:1 extension

You will need to replace the motor which comes with the gear box with the solar motor (I don't know how difficult that will be).

And you will need to gear down the output a bit more with a couple of pulleys and a belt.

Keep it simple to begin with! You can easily add sophistication when you get the simple tracker working.

This solution has the added advantage that you need no external power supply.

The exchange rate is about $1.60 to the pound at the moment, but unfortunately the site I have got my prices from will charge you a fortune in postage outside the UK, so, you will need to find a similar local supplier.

I am a professional electrical engineer wit many years experience in control circuits. This circuit might have done 30 years ago but it is no tonly too complicated but can be doen much more simply in the digital domain.

All you need is a simple micro controller with a few A/D channels, the photo cells shown, a few resistors and some H-bridge circuits to drive the motors.

An eval board from someone like silicon labs could be used and they have a nice debugging environment and 12 bit A/D's for well under $100.

The photocells would be series connected with the resistors to set up a voltage divider. This can probably go straight into the A/D. You have to do the math and see what it looks like. You might need a stage of amplification, but most likely not, with a 12 bitter. Then you'll have to write some code in C to sample the levels and move the motors.

The H-bridge inputs can probably be driven straight from the digital IO's on the micro, but it would be more robust to add some isolation. That's another discussion. I guess your circuit achieves that by using relays. You could also use some OPto22 modules. Search Opto22 on ebay to find some incredibly inexpensive ways to drive electrical equipment. In fact you could even do the entire thing that way using an analog IO board, an analog brain board and some analog in modules, a digital IO board, a digital IO board, digital brain board, and some output modules of the voltage flavor that suits your motor. With this you could control from your PC and a serial port.

Just a few other ideas on how to do this that are much better. While writing this it occurred to me that you might not know how to write code.

So, if you search the net for a design using some of the words or descriptions use above, you may find a digital design done with code ready that will be much easier to wire up, not have the weird quirks an improperly built analog circuit will have and maybe provide you with a learning path to something more useful.

a simple micro controller with a few A/D channels...
C'mon I think we are dealing with someone new to electronics here. The simpler the better, there are plenty of simple analog circuits, what he needs is a simple cct with a very good and detailed explanation of how it works , or a quick primer in faultfinding techniques.
I'd guess writing assembler is waaaay beyond expectation.
Del

Yes, I would do it with a PIC or Arduino single chip processor (their development system is cheap and simple). But, this guy has plenty of difficulties with simple DC circuits. Sensors first, H bridge driver next, hysteresis introduced, end switches for refinements, light sensing for wakeup, for completion. A PIC can do it with the lowest parts count and flexibility indeed. But, one has to have DC circuits down pat to do it that way. Troubleshooting programs is enough alone!

well i took apart the cir, and them put it back together, I must have had it wired wrong. This time every thing worked, both leds came on, and when I put my finger over I think it was the west photo cell, LED 2 would come on then took my finger off and led2 would go off. But now LED 2 wont light at all.

I changed out the LM339 and same, I changed out Q3 nothing .What causes LED2 to come on?

tks

I don't mean to sound mean, but the secret to fault finding is understanding.
Break the circuit down into stages and check them one at a time.
So, to answer your question, the potentiometer VR1 adjusts the voltage into IC1a (+), this is compared with the voltage on the (-) pin which comes from the photosensitive resitor PC2. So adjusting VR1 or the light onto the sensor can cause the output of IC1a to go up or down.
You need to be testing in the appropriate light conditions and to see what is happening. Ideally need an oscilloscope, but for this sort of circuit a good multimeter will help.
Changing components randomly isn't the way to fault find, understanding and carefull examination are the key. Trust me I've been there, done that about 40 years ago and regularly ever since!
This isn't a criticism but I'd say you need to improve your understanding or use a simpler circuit which you can follow.
Playing with this sort of thing is a great way to start learning about electronics, but if you don't want to learn about electronics it's a nightmare.
Electronics is easy in theory, just get a circuit diagram, build it up and it works.
Nah, hardware seldom works first time (and software never does).
Welcome to my world.
Del

Del cat, I understand, and I take you words in understanding that I should learn more about what the parts do, and I have been reading up on many of them.But the transistors are new to me, and now I know most are just switches.

I got most of it working, and I found one mistake that I made. hee hee , I put the anode in the wrong spot, so now both LEDs are lighting and dimming when they are suppose to. Now I just have to check my voltage to my relays, it seems that they/ r1 isn't getting all the voltage to pull in the contacts.That should be easy.[ ha ha I hope.]

Just want to thank everyone/. Most people are very nice. yes your a good guy. lol

Hi, After searching online for circuit ideas. Me and my lab partner decided to this for applied capstone project. After reading these post can you guys recommend any other project ideas.