View Full Version : Please Help me

April 1st, 2005, 08:22 PM
I need an Seimens S7 program to do the following steps. the adressing does not matter, as long as it is in ladder form!

1)extend a cylinder for 4 seonds every time control switch goes on. needs to stay on even if input switch is turned off
2)extend a second cylinder two seconds after first cylinder extends. needs to retract when first cylinder retracts.

3)setup a counter that counts down each time switch one goes on, and counts up each time second switch goes on.

4)after three cuations of the counter, from the first witch, extend third cylinder, time for three seconds, and then retract. this cylinder requires seperate solonoids to extend and retract. each solonoid must be ctivated for exatly 500 miliseconds. use the counter output to drive the three second timer.

Thanks your saving my life!

April 1st, 2005, 08:51 PM
Man...you have to learn sometime!
Are you a student????

Sounds easy :p

For whoever ends up doing it for you - are you using spring return solenoid valves or APB?

April 1st, 2005, 11:02 PM
Guest Student,

Here is a sample S7 program. It probably has a few errors, so be sure to study it until you find them.

April 2nd, 2005, 12:59 AM

I see that you used microwin for your example, maybe our guest wanted it in Step7 :huh:

Still, you have given him a start, after all he wouldn't want you to do all his homework for him, now would he?


April 2nd, 2005, 01:24 AM
Microwin is Step 7. It says so right on the very first screen menu (Quote: "STEP 7-Micro/Win32")! Maybe it is stripped down a little, but it should be okay for a student who doesn't care what addresses s/he uses anyway.

Fred Floggle
April 2nd, 2005, 01:50 AM
Send him a copy of S7 as well - you have done everything else for him !
Hope you are available to take his exams for him .

April 2nd, 2005, 02:02 AM
If you think I have done everything for the student, then maybe you need to take the course also. There are some errors in my program not so obvious, but maybe a challenge for a student. If he turns it in like it is, he will probably flunk out.

P.S. I could be available for exam-taking for a small gratuity:rolleyes:

April 2nd, 2005, 02:15 AM
you can upload this prog for furter referance to PLCs.net


jolio ST
April 2nd, 2005, 02:24 AM
Unregistered wrote:
I need an Seimens S7 program to do the following steps. the adressing does not matter, as long as it is in ladder form!
Thanks your saving my life!

Really...If you are a student, need not fret about not handing up your assignment. You won't die, just fail the work and maybe your exams. I never hand up my tutorials for one module and I didn't need people saving my life. But I passed that module still.
Different case if you are working though....
So it's just my view.

April 2nd, 2005, 02:36 AM

I cannot upload the Step 7 Microwin software program, as it is proprietary and copyrighted by Siemens. I could upload my Cylinder Control project file if it would help any. Could you not type it in yourself? It would be good practice for learning how to program.

Fred Floggle
April 2nd, 2005, 02:54 AM
The guy isn't even trying - I thought it was a prerequisite here that an attempt had been made to solve a problem before demanding help - this guy can't even be bothered to register . Why should you (or anyone) do more than the student is prepared to ?

April 2nd, 2005, 02:58 AM
Hey, I never do it ONLY just for the students. If I didn't enjoy the challenge of writing the programs, I would be out of here in a flash.

As far as I know, it is not one of Phil Melore's rules. I don't know who made that one up, but it is okay with me if they want to follow it. I think each case has to be judged on the situation. If s/he doesn't get help here, will they then sit down and work on it themselves? Probably not, because the ones who will do that aren't here on this site. They are busy working it out for themselves. For the others who need help, if all they get is grief, then any chance to influence students in the right way is lost. I am assuming here that the goal is to help (not aggravate) anyone with problems.

Students are always looking for a free ride and a short cut. Our goal should be to make it look easy (otherwise they will quit coming here) but to not be without some effort.

April 2nd, 2005, 10:18 AM
I have debated this with myself and others. I came to the foregone conclusion that everyone looks for examples on "HOW" to do something. Books and manuals are not always clear. Each person learns in a different manner over different time periods, what may be obvious to one person isnt to another...vice versa.

I will offer examples, some with errors and some that wont exactly match what the student needs but may offer enough for them to complete the assignment.

I have Simatic S7 and this would be a good excuse for me to write something with it as an exercise.

If you teach, explain, provide or just get involved its possible you may learn something yourself.

This is Rule #7 for this site.
7. Again, Please, no advertising, name calling, rude behavior, foul language, or disrespectful posts.
Wouldnt you agree that the flaming and derogatory remarks violate this?
In many cases the "students" are young people, some even in high school. They need guidance from those older and experienced, not disillusioned.

Adult educated professionals but you feel its necessary to demean others.... Do not judge others lest ye be judged.

Fred Floggle
April 2nd, 2005, 12:58 PM
I don't know who the last post was directed at - but , I see nothing disrespectful or rude on this page . Since the registration procedure here is simple , I would think that it would be polite to at least take the troube to do this in return for help - as we have all discussed on many occasions , no one minds helping if there is a bit of effort shown - " I did this much , but can't get further" is the spirit .
Now , I may well be wrong , but this question looks like 100% homework rather than real life - and if this is the case , then the answer is not giving everything on a plate .
This problem is not too difficult to think through , and you have to ask yourself if you are doing anyone any favours by not encouraging thought . The flip side of the coin is that id this is going into industry , the same thing applies - the poster needs to think about what he is doing , he is messing with air cylinders (could be big dangerous finger crunching ones) , and there are implications as to safety and unexpected operation that have to be considered , and half copying someone elses work is not the way to realise about these other considerations .
I wouldn't ask anything here without at least try to think about it first myself - I consider it a courtesy to those who take the trouble to reply .
I think I won't make any more mention regarding this subject - the students will find out the hard way regarding thinking and consciousness when they hit the exam paper or industry - being able to copy things parrot fashion is not the answer.

April 2nd, 2005, 01:41 PM
I think youll find rule 7 was also broken here

Post #13


Fred Floggle
April 2nd, 2005, 02:24 PM
Yes - I suppose you could say it was - if there wasn't alternative software available now for the siemens "jurassic" range - it is like asking what leather was used in SU carburettors ( SU actually stands for Skinners Union - a leather concern ) hardly important now that everything is made of nitrile etc - but the poster has an interest in things bygone .
The original poster here has no interest , maybe except an easy ride .
Why not let the original poster expain why he can't make the effort to think about timer and counters - I would expect this post of somebody who had never seen a PLC before - maybe this is the case - why not explain ?