Traffic Light Assignment

Hi everyone Iam new to this forum and i need big help. I have to do this assignment and pls someone help me out. Program the PLC to run the traffic light simulator using a timer. the program should incorporate call buttons and call record lights. When the call button is pressed the call record light should come on. On the next cycle the appropriate walk light should come on and the call record light should go off.I have attached the assignment file pls help Thanks .

Go to the bottom of this page and search for traffic light. I think that will give you enough to chew on.

thanks but didn't help much

akumar43,

Welcome to the forum.

As Norml suggested use the search function on this site, but I'm requesting that you use traffic light in the key words section and Lancie1 as the user name. http://www.plctalk.net/qanda/search.php?searchid=616275

Lancie1 contributes a lot of his time to students that 1.show what they have done 2.show some effort on their part.

Hmmm, for me the search is on the top of the page. Maybe because I'm using firefox.

Akumar,

If you look in the "Downloads" under Allen-Bradley, you will see a LogixPro Traffic Light program that has the Walk/Don't Walk lights. Then you will need to adjust the various timers to match your timing diagram, and also remove all the fancy things that your instructor did NOT ask for on your assignment. It should be easier to remove things you don't need, than figure out how to do the things that you DO need.

....using a timer.

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Do you mean using ONE timer, or do you mean to use the "timer" method? The traffic light can be done using one timer, or it can be done using 4 or more timers (most common).

The program should incorporate call buttons and call record lights. When the call button is pressed the call record light should come on. On the next cycle the appropriate walk light should come on and the call record light should go off.

Click to expand...

The "call" buttons are in the Downloads program. The "Record Call" light will need to be added, but should be easy. Look for the B3:0/4 and B3:0/7 relays (Walk Requests) and add lights in parallel with those.

thanks but didn't help much

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For our HQC Team (Homework Quality Control Team), would you be so kind as to define what you mean by "much" by selecting one or more of the folowing statements:

(1) "didn't help much", as in "it wasn't worth a penny".

(2) It helped some, but I need much more. I need someone to step me through it one rung at a time.

(3) Did not give me a place to start, and being a student who recognizes that homework is assigned only for my benefit and to learn anything I must do it myself, then I did not find much info here and I don't know where to start.

(4) I am not really interested in knowing this stuff, but I am doing this course for other reasons (girl friend thinks PLCs are cool), and I just want to get through it without learning anything much.

(5) I did not really search very much, or I would have found dozens of discussions and many program samples on the traffic light problem.

Thanks I found the program but unable to open which program I need?

...Program the PLC to run the traffic light simulator using a timer

Click to expand...

If you have a "traffic light simulator", then it is likely to be LogixPro from http://www.thelearningpit.com/http://www.thelearningpit.com/http://www.thelearningpit.com/http://www.thelearningpit.com/


There is also an RSLogix (RSS file) version of the traffic light in the Downloads. What PLC brand are you using in your school?

May suggest that you attempt to do the homework yourself? Give it a shot, you might find that you enjoy the challenge. If you get stuck, then ask for help. Just make sure to show some progress.

If you don't know where to start, draw a sketch, and asign I/0 points to the drawing. Then start with one light, look at your chart, drawing, and scratch your head a little.

BTW, my students know not to turn in the program listed here in the download section.

Good luck.

How about a special homework section?

Wait, that got shot down a couple of years ago.....

Not sure it would matter I don't believe there are too many instructors out there that aren't familiar with this site.

IIRC, we had a thread here quite some time ago where a student posted his homework question and the instructor saw it and replied not so kindly .

Alaric said:

IIRC, we had a thread here quite some time ago where a student posted his homework question and the instructor saw it and replied not so kindly .

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Like in post #8 above ^^^

I had no intention of being rude. However, for those of you have been out of school for a while, things have changed. The difference is that for some reason most kids believe that the only way to solve any challenge is to do a search on Google, and then copy the results. I see this way too often.



I had one term paper submitted that had alternating paragraphs copied from four different web sites. Oddly enough it was a fluid read, and had a coherence that did not exist in any of the four sources. Still this is plagiarism. The guy went through all of that trouble for a zero. When I asked him why, the response was that he thought that was how it was done.



Every semester I see a group of kids that mean well, but have no idea of what original work is. Granted the stop light puzzle is common enough, I had to write one twenty years ago in an Austrian apprenticeship program. It is the process of solving the logic on ones own that serves as an education, not the ability to copy the answer. My own children and students are somewhat puzzled because I force them to solve problems on their own. My twelve year old daughter had to create a graph in excel for her science project. I opened Excel and showed her the basics of graphing. She did the rest, and then taught most of her class how to create a graph. Her Power Point presentation went much the same. She is very proud of work well done. Most other parents grumbled about having to create a power point, and do another science project. BTW, she won three academic awards this year.



If you are wondering, I use LogixPro, and the traffic light simulator is there, I do not use this as a homework assignment or a class lab. The simulation is enticing enough, and most of my students tackle this one on their own. They love the crashing cars.

I do agree with what is being said in this message. Kids nowdays are not taught how to think on their own. My daughters have tried various stunts like this over the years and each time they would loose some of their enjoyments. Such as they might loose 2 weeks of internet connection, or 2 weeks of phone or something like that. They think I am being tough, rude and ignorant. But eventually they will come around. Or at least I hope they do.

Its to bad that things are not as they were in my day of going to school. Yes our one lab was to do a traffic light and yes we could have used a PLC but the teacher was old school and for this first project he made the class use old analog timers and relays. You had to draw and plan out your whole project including the walk/dont walk signals. Once you were able to show that you could properly accomplish this task and it worked to the teachers expectations along with all documentation then the second lab was to the same thing but using a PLC. He did this on a number of labs. This way he said you learned from the past to make the future better. He had a lot of sayings like that. But the one thing he definately did was made sure you did your own thinking.

Kind of like our english teacher. Start out writing a 500 word essay, then after that was turned in and graded take that same essay and knock it down to 250 words but be able to convey the same message. Once that was done and graded now do the same but take it down to 100 words. It was quite a challenge and skills like this in todays day and age are quite hard to come by.

I mean look at the IM community and the slang and abreviations they use. No wonder our english language is going down the tubes along with our educational standards.

plchacker said:

I had no intention of being rude. However, for those of you have been out of school for a while, things have changed. The difference is that for some reason most kids believe that the only way to solve any challenge is to do a search on Google, and then copy the results. I see this way too often.



I had one term paper submitted that had alternating paragraphs copied from four different web sites. Oddly enough it was a fluid read, and had a coherence that did not exist in any of the four sources. Still this is plagiarism. The guy went through all of that trouble for a zero. When I asked him why, the response was that he thought that was how it was done.



Every semester I see a group of kids that mean well, but have no idea of what original work is. Granted the stop light puzzle is common enough, I had to write one twenty years ago in an Austrian apprenticeship program. It is the process of solving the logic on ones own that serves as an education, not the ability to copy the answer. My own children and students are somewhat puzzled because I force them to solve problems on their own. My twelve year old daughter had to create a graph in excel for her science project. I opened Excel and showed her the basics of graphing. She did the rest, and then taught most of her class how to create a graph. Her Power Point presentation went much the same. She is very proud of work well done. Most other parents grumbled about having to create a power point, and do another science project. BTW, she won three academic awards this year.



If you are wondering, I use LogixPro, and the traffic light simulator is there, I do not use this as a homework assignment or a class lab. The simulation is enticing enough, and most of my students tackle this one on their own. They love the crashing cars.

Click to expand...

Pls can anlone tell me how B.C.D is concerted for eg. 127 will be 0001=1,0010=2and 0111=7
To BCD-encode a decimal number using the common encoding, each digit is encoded using the four-bit binary bit pattern for each digit. For example, the number 127 would be:

0001 0010 0111 How this works