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Forum Index : Electronics : solar tracker
| Author | Message | ||||
| conntaxman Newbie  Joined: 04/08/2011 Location: Posts: 5 |
Need help figuring this cir out at this link, its a sun tracker. http://www.projectcircuitpack.yolasite.com/automatic-solar-t racking-system.php Their are TWO ic ne555 circuits and then they say they both connect to the CD4017 at pin 14. The two small circuits are very easy and the 3rd. But do they both connect to pin 14. tks John |
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powerednut Senior Member  Joined: 09/12/2009 Location: AustraliaPosts: 221 |
Yes the 555 circuits both connect to pin14 of a CD4017. It seems to me that their should be one of the cd4017 circuits for each axis as you will need one motor to move the panels in the horizontal plane, and one motor to move the panels in the vertical. the paragraph under the cd4017 circuit seems to say this. working link here |
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| conntaxman Newbie Joined: 04/08/2011 Location: Posts: 5 |
Hi Power. after reading it a few times , seen he is using 2 motors. Another thing if you can help me out is ,at the end of the page on the picture of the CD4017 , the lines that Connect "ALL" the pins together. then I can see the 4.7K resistor ,but What are the TP120 things? Then they connect to Each coil of the ... 2... motors. What im going to be doing is just build the Horizontal ,I don't need the vertical part. I hope that it works with just one. Tks for the reply. I built one of a different type cir and it dosen't work.And then found out that other people built the same and theirs didn't work either. John |
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| powerednut Senior Member Joined: 09/12/2009 Location: AustraliaPosts: 221 |
Okay, so your talking about this image? 
thats certianly a strangly drawn schematic, which makes it hard to understand. I'm a newb, so I don't know if it'll work or not as drawn. Anyway, to answer some of your questions: The TP120s are darlington pair transistors. For our purposes here you can think of them as high power transistors. I think he is using them in a h bridge configuration, which switches the coils on the motors alternately to +V and gnd. A similair CD4017 based stepper motor driver can be found here: http://pcbheaven.com/circuitpages/Simple_Unipolar_Stepper_Mo tor_Full_Step_Controller/ There is a nice video which explains whats going on. You may want to have a hunt around the net for similair stepper motor drivers to see if you can find a good explanation of how its supposed to work, and then try and figure out what that guy has done. or you could just email him and ask. *edit* i'm certain that circuit wont work as drawn. the direct short between +Volts and ground is a bit of a give away. *edit2* actually i'm pretty sure its supposed to be +Volts again. you need somebody better at interpreting schematics than me *edit3* stuffed if i know. |
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| conntaxman Newbie Joined: 04/08/2011 Location: Posts: 5 |
That was a nice vid. I was thinking of using a regular low rpm DC motor,I'll get the forward and reverse just by changing the + and - wires. So i wont need the stepper motor control part. I just need the left and right / forward and reverse part to go east and west.Dam i just ordered 2 of the CD4017. oh well. |
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| powerednut Senior Member Joined: 09/12/2009 Location: AustraliaPosts: 221 |
umm. well in that case you don't really need the 555 circuit either - its just there to generate the square wave (like in the video) to feed into the CD4017 which switches the right coils in the stepper motor on and off. |
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