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bryan372002

Check over this Please

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ok I wrote this and it does what the instructor wants except, the condition where if switch 2 is made output 0 will remain on even if switch 2 is turned of as long as switches 0 and 1 are still true. but as wher switches 0 and 1 turn it off in the beginning now they are to keep it on......if a one shot will work i cant figure out where to put it. Ok would you like me to post it as it is written example is when light 1 is on y0 is true or post it like it is suppose to read, example when switch 1 (or input 1) is on output 1 is on?

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taking it at a community college, what you mean by nothing in writing? if you are referring to the specs for this project, what Lancie posted earlier are Word for Word what is on the sheet. If need be i could scan it and attach it.

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Please Look over this it seems to meet all conditions as i know them, Thanks TW It was re-reading your post about latching bits that brought this to mind. It should work as follows if switch 3 and switch 0 and switch 1 are on then output 0 is off. if switch 3 and switch 0 and switch 1 and switch 2 is on the output 0 will be on and remain on even if switch 2 is turned off, as long as switch 0 and 1 are on.

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I took the time to do this assignment as Lancie has posted. I don't the spirit of this lesson is to use latch and unlatch bits. I think its a nice little program to learn series, parallel and a holding contact. Though you can do it with the latch and unlatch. Break down this part if the assignment. 1. When lights 1 and 2 are turned on Y1 will be on This is easy to do correct. Create your rung with just this. 2. Y1 will be on and remain on after either light 1 or 2 are turned off. This is where a holding contact is going to be used, right. 3. The only way to turn Y1 off after it is on is to turn light 3 on. There has to be a way to break the holding contact. This is where Light_3 will come into play. hint|\| 4. If Light 3 is on and light 1 and 2 are on Y1 will be on. If you have done the above is this not already the way its working. I think if you break the task into small sections it wont seem so hard to do. Start your rungs with the coil first then think if the things that qualify that coil to come on then add those contacts.

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Bryan - I read this post tonight for the first time. Being at home for a week of vacation means I do not have RSLogix available, but I found your stated problem from class posted by Lance to be a 5 minute brrain tease before I had a working program on paper. I'd suggest you get logic that works for the non reverse case first and then create a parallel branch for the reverse case. Keep in mind I have programmed computer for 30 years {ask you instructor if he remembers PDP-11 and Intel 8046} and PLC's for 20 plus. So I have an unfair advantage. I am missing the correlation between your sample and the problem. You should have rungs for O:0/0 , 0/1, 0/2, 0/3, 0/4 and 0/5. I used B3/1, B3/2 and B3/3 for lights in my solution. And I:1/3 for X3 the reverse Switch and I:1/4 for X4 the Flash Switch. It is handdrawn on paper right now. Will clean up and maybe scan tomorrow or later.

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It seems like the "spec" has changed form the last thread at this site you posted: http://forums.mrplc.com/index.php?showtopic=8947 lol, honestly, I can't keep track anymore. Its like shooting at a carnival duck gallery. IMHO, I believe it gets very difficult trying to anticipate (guess) what the instructor (customer) is asking for beyond what he has specifically written down and agreed to. This parallels real work situations that you'll run into. Mind reading is not in the job description. I'd be very interested to see what the instructor believes is the correct answer to his question. Hopefully he knows that there can be many correct answers depending on who submits them. Please post it if he provides one.

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Reread this post again this morning when I was fully awake. There is definitely an anomaly in the description of Y1. I attempted in mnemonic using notepad to formulate an answer to this problem as atated in the complete spec posted earlier. Since the underlying thought of the X3 input is to reverse the logic the Y1 Reverse case would state as follows IMHO: IF Lamp1 and Lamp2 are off Y1 is OFF. Once Off Y1 remains off for a long as Lamp3 is on. Given this I arrived at the following logic. SOR BST XIO X4 BST XIO X3 XIC Lamp1 NXB XIC X3 XIO Lamp1 BND NXB XIC X4 XIC Flasher_ON BND OTE Y0 EOR SOR BST XIO X4 BST XIO X3 XIC Lamp3 XIC Lamp1 NXB XIC X3 BST XIO Lamp3 NXB XIO Lamp1 BND BND NXB XIC X4 XIC Flasher_ON BND OTE Y2 EOR SOR BST XIO X4 BST XIO X3 XIC Lamp3 XIC Lamp2 XIC Lamp1 NXB XIC X3 BST XIO Lamp3 NXB XIO Lamp2 NXB XIO Lamp1 BND BND NXB XIC X4 XIC Flasher_ON BND OTE Y3 EOR SOR XIO X4 XIo X3 XIC Lamp1 XIC Lamp2 OTL Y1 EOR SOR XIo X4 XIo X3 XIC Y1 XIC Lamp3 OTU Y1 EOR SOR XIO X4 XIC X3 XIO Lamp1 XIO Lamp2 OTU Y1 EOR SOR XIO X4 XIC X3 XIO Y1 XIO Lamp3 OTL Y1 EOR SOR XIC X4 XIC Flasher_ON OTL Y1 EOR SOR XIC X4 XIO Flasher_ON OTU Y1 EOR SOR BST XIO X4 BST XIO X3 XIO Lamp1 XIO Lamp2 XIO Lamp3 NXB XIC X3 BST XIC Lamp1 NXB XIC Lamp2 NXB XIC Lamp3 BND BND NXB XIC X4 XIC Flasher_ON BND OTE Y5 EOR SOR BST XIO X4 BST XIO X3 BST XIC Lamp1 NXB XIC Lamp2 NXB XIC Lamp3 BND NXB XIC X3 BST XIO Lamp1 XIO Lamp2 NXB XIO Lamp2 XIO Lamp3 NXB XIO Lamp3 XIO Lamp1 BND BND NXB XIC X4 XIC Flasher_ON BND OTE Y4 EOR I am about to leave for Walkabout until after 9/11 hope some one can convert this to Logix while I;m away and maybe poke holes in it. Edited by BobLfoot

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Bob, you couldn't go back to my water drains first? http://forums.mrplc.com/index.php?showtopic=8987 Kidding of course, I hope you have a good holiday Here is Bob's sample in RSS. I don't have a PDF converter on this PC so perhaps someone else can get it into PDF format for those without RsLogix 500. I left the X0/Y0 addressing so it will not verify but should line up with everything else that has been stated BobSample.RSS

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Hey TW - Do you see the anomaly of Y1 description in the sped. Thanks TW I will - Went on the same walk about 2 years ago as a pilgrim, now going as a guide. Leave in a couple hours. Always kind of fun to go without "modern encumbrance" for a weekend. Edited by BobLfoot

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ok TW but this is the last time...(just kidding ) BOBSAMPLE_1_.pdf

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Thanks. You would think eventually I would get everything installed on that computer

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Thanks TW and panic Mode. With the Walkabout I left work at work. The conversion looks great. Hope that Bryan posts again to let us know how class is going. I vaguely remember that time when it is very frustrating until "it" jsut clicks.

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Hey Bob and everyone else involved, Thanks for all the help, It going ok, finally got that project behind me and have moved on to project 2, an anti-tie-down project, will be glad to post it and my solution if You all want. The instructor for this class is really messing with Our heads I think with the specs he is giving, He leaves so much to be assumed, but yet you are lucky if you can corner him to get more specific info.

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Bryan - None of us here wants to be in the business of doing anyone's homework. That being said we'd all love to help and nurture a new PLC programmer into the brotherhood. I think you'll find that most of the members here share that sentiment. Glad you solved the anti-tiedown issue. As far as the instructor "messing with your mind" and being vague on your specs. He is probably just trying to inject some "real life" into the classroom. After all in "real life" Some simple rules exist. 1. The customer is always right. At least in his/her mind until taught/made-to-see otherwise. 2. The customer seldom knows how to describe what they want. 3. What the customer asks for is usually only a part of what they want. 4. When the customer is wrong -- SEE RULE #1. Good Luck. BTW you are stuck between TWControls in VA and Ken Moore in SC If I read my map correctly. Good part of the country. Edited by BobLfoot

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One customer replied with the following statement, and I've never forgotten it: "Yes, that's exactly what we asked for. But, that's not what we wanted!"

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And did they expect you to pay for their want also?

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I think I would have to pass that one on to someone above me. I would have a hard time not making a smart comment in my response

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Thanks again I would not want anyone to do my homework thats half the fun of learning, Just need some direction sometimes, and have you all critique my work and tell me of my mistakes and or bad techniques. I'm trying hard to learn all i can. maybe the hard way, getting bits and pieces here and there even some thru trouble shooting at work, wish i had learned this trade before I hit middle age....lol might have sunk in a lot better. and sometimes I think i try and over think whats not as hard as It sounds or seems. but i'll get there. my goal right now is to be able to connect to PLC's and work for trouble shooting purposes and eventually make small changes to the programs when needed. BUT dont worry Im not about to take lives into my own hands without proper training and supervision......lol Thanks you guys for your Help

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Jstolaruk - industrial finagler?

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having fun with the thesaurus

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Just curious

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