# Learning ladder logic.



## CYoung (Apr 19, 2013)

Try this website:
http://www.thelearningpit.com/

The simulator they offer is pretty cheap and offers some good real world exercises.


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## ScooterMcGavin (Jan 24, 2011)

If you want to jump right into the deep end of the pool this book is hard to beat for the price (Free). Its based on Allen Bradley PLC's although a lot of it applys to any brand.

http://claymore.engineer.gvsu.edu/~jackh/books/plcs/pdf/plcbook5_1.pdf


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## CYoung (Apr 19, 2013)

scameron81 said:


> If you want to jump right into the deep end of the pool this book is hard to beat for the price (Free). Its based on Allen Bradley PLC's although a lot of it applys to any brand.
> 
> http://claymore.engineer.gvsu.edu/~jackh/books/plcs/pdf/plcbook5_1.pdf



Thanks for link. Just downloaded book


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## John Valdes (May 17, 2007)

SEREMan2000 said:


> I started a new job working in a paper mill and have been given the chance to learn ladder logic. Can anyone give me info on where I can find books and possible software to play around with?


Your best teaching tool is right in front of you. The machines that reside in your plant.

Find the machine drawings and use them to physically see how each line of the schematic is terminated.
While your at it. Correct any drawing discrepancies. 
Like the guys that changed wiring without making the changes on the drawing.

You don't need anything but what sits in front of you every singe day at work.


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## EBFD6 (Aug 17, 2008)

SEREMan2000 said:


> I started a new job working in a paper mill and have been given the chance to learn ladder logic. Can anyone give me info on where I can find books and possible software to play around with?


Join the forum over at plcs.net.

Lots of info. Most of it will probably be over your head (it's certainly over mine) but deffinately worth a look. They have an area where you can learn basics about plcs/ladder logic and plenty of guys to ask questions to in the forums.


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## denny3992 (Jul 12, 2010)

EBFD6 said:


> Join the forum over at plcs.net.
> 
> Lots of info. Most of it will probably be over your head (it's certainly over mine) but deffinately worth a look. They have an area where you can learn basics about plcs/ladder logic and plenty of guys to ask questions to in the forums.


Thanks for info


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## Wirenuting (Sep 12, 2010)

John Valdes said:


> While your at it. Correct any drawing discrepancies.
> .



In Pencil please.


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## willf650 (Jul 14, 2013)

If you want to invest a little money to learn try automation direct and buy one of there click plcs. They are around $80 last time I bought one and the software is free. They are an easy way to get your feet wet with a live controller. Even if you don't buy an actual plc you can still use the software in simulation mode.


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## chicken steve (Mar 22, 2011)

Mike Holt sold software in the past, i thought the way it activated every component in order was a great learning tool....~CS~


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## dthurmond (Feb 7, 2011)

willf650 said:


> If you want to invest a little money to learn try automation direct and buy one of there click plcs. They are around $80 last time I bought one and the software is free. They are an easy way to get your feet wet with a live controller. Even if you don't buy an actual plc you can still use the software in simulation mode.


Automation direct offers a three day class all over the country . I took one in Atlanta in 2011 and it was a pretty good class . They also have good tech support .


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## dronai (Apr 11, 2011)

leroy843 said:


> Congratulations on your promotion. Check out this site for some ....................... and good luck.


Is that the same as a WTF instruction ? (from your site)
 
*Definition*
The NOP is a ladder logic rung instruction that does nothing. Place it anywhere on a rung or branch and it will do nothing. Have fun with it. Use it as a placeholder for a search. It can be used in place of an output instruction just in case you want your logic to do nothing.


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## karl_r (Nov 5, 2012)

willf650 said:


> If you want to invest a little money to learn try automation direct and buy one of there click plcs. They are around $80 last time I bought one and the software is free. They are an easy way to get your feet wet with a live controller. Even if you don't buy an actual plc you can still use the software in simulation mode.


could you please elaborate a little further? I'm doing resi&commercial but I want to go industrial, and PLC is the way.


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## ScooterMcGavin (Jan 24, 2011)

karl_r said:


> could you please elaborate a little further? I'm doing resi&commercial but I want to go industrial, and PLC is the way.


I would start by downloading the logix pro simulator mentioned at the beginning of the thread. It has simulated processes that fight back and you get a 2 week trial to try it for free. Plus its based on the Allen Bradley logix platform which is pretty prominent here in America.


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## Safari (Jul 9, 2013)

John Valdes said:


> Your best teaching tool is right in front of you. The machines that reside in your plant.
> Find the machine drawings and use them to physically see how each line of the schematic is terminated.
> While your at it. Correct any drawing discrepancies.
> Like the guys that changed wiring without making the changes on the drawing.
> You don't need anything but what sits in front of you every singe day at work.


john this is the second time am reading a similar post from you.i remember the first time i read this.i started implementing it directly.luckily almost all of our machines are plc based.but after going halfway i still feel am not able to program one. am one of those guys untill i touch with my hands i cannot believe,there are so many plc's kit online i dont know whichh one is good.most of our plcs are siemens S7 300 and s7 400 series,we just have one micrologix and sadly most youtube lesons dwell on micrologix,


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## ScooterMcGavin (Jan 24, 2011)

nickson said:


> john this is the second time am reading a similar post from you.i remember the first time i read this.i started implementing it directly.luckily almost all of our machines are plc based.but after going halfway i still feel am not able to program one. am one of those guys untill i touch with my hands i cannot believe,there are so many plc's kit online i dont know whichh one is good.most of our plcs are siemens S7 300 and s7 400 series,we just have one micrologix and sadly most youtube lesons dwell on micrologix,


When you say you don't feel that you can program one do you mean a machine, or you can't program anything onto the PLC? I've been told that Siemens is the most popular PLC outside of the US. Here Allen Bradley still rules the roost. I have also been told that Siemens is designed for the engineer and Allen Bradley is designed for the electrician. I have never worked with Siemens S7's so I can't speak from personal experience.

If you have figured out how to navigate the S7 software but just don't know how to design the logic then really any trainer will work even the logix pro thats Allen Bradley based. What you need to learn are the commands, OUTS, SET, RESET, TIMERS, COUNTERS, COMAPRES etc etc. An Allen Bradley timer and a Siemens timer all have the same basic features its just what they are called or how they are accessed thats different. 

Start with some very simple programs such as a start/stop with a seal in, then add a 10 second time delay before it starts, then have it run light A for 10 seconds, and then light B for 5 seconds and the stop. Super simple things that will let you get familiar with the commands of the PLC. Once you get comfortable with that you can start combining different commands together to make more complex programs.

One thing I did that really helped was recreating actual systems/programs that we have at work. For example we have a 4 pump sequencer where the operator can choose in which order the pumps start and then they start sequentially. It took me a little while but I finally got it. After I had my version working I checked it against the actual program and compared how it was done to get ideas on how it could be done different or better.

One thing that you should do is list all your inputs and outputs. Then write a functional description of how your machine should operate, and then program from there. Writing it out makes you think it out logically without being overwhelmed by trying to also write the program on the PLC at the same time.

John's advice is spot on. I will just grab the prints for a system and study them and figure how the system is setup in my downtime. When the system does breakdown, I already have an understanding of how its setup and how its supposed to work. It makes troubleshooting so much faster because I am not trying to figure out how it works in the heat of the battle. I also play little scenarios with myself. If relay X where to quit working what would it do to the system. It helps you get a much deeper understanding of the system.

All the information is out there you just have to go looking for it and be motivated enough to use it. People ask me all the time where I went to school and I tell them the University of Google. At first they think I am being an ass, but I tell them its the god honest truth.


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## Safari (Jul 9, 2013)

scameron81 said:


> When you say you don't feel that you can program one do you mean a machine, or you can't program anything onto the PLC?
> _* i meant the plc sorry,however the start stop of motor i can write the ladder not on the plc though.one thing i want to do is have a motor, the relays, have my i\o modules and see the motor running and stop.this i haven't done**.please recommend an affordable kit. i will have to buy it online apparently we don't have them*_
> I've been told that Siemens is the most popular PLC outside of the US. Here Allen Bradley still rules the roost. I have also been told that Siemens is designed for the engineer and Allen Bradley is designed for the electrician. I have never worked with Siemens S7's so I can't speak from personal experience.
> 
> ...


this is great info,thanks am happy to be in ET.thanks:thumbsup:


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## HARRY304E (Sep 15, 2010)

nickson said:


> this is great info,thanks am happy to be in ET.thanks:thumbsup:


:thumbsup::thumbsup:


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## uconduit (Jun 6, 2012)

I read up on the whole NEMA vs IEC thing a while back. From what I understand, the European continent was pummeled with during the mid-20th century in large part by Boing manufactured airplanes that dropped a lot of high-quality bombs made right here in America by women in large factories. 

This created a demand for electrical work to rebuild the stuff that America, her allies, and the Axis powers decided to do demolishion work on. The problem that the Euros had was too many unemployed engineers and too little money (the Euros used large portions of their gold reserves to buy American dollars, increasing the gold held in American banks to about 50% of all mined gold at the time). The IEC devices were made to be as cheap and weak as possible while still being able to do the job. It took an engineer to size the exact device for the task, making selection unnecessarily complicated, and since they weren't supposed to be repairable it also meant a new device had to be manufactured for every failed device providing an ongoing market for IEC devices.

I'm not trying to start an argument. I'm just trying to explain why I believe things are different.


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## HARRY304E (Sep 15, 2010)

uconduit said:


> I read up on the whole NEMA vs IEC thing a while back. From what I understand, the European continent was pummeled with during the mid-20th century in large part by Boing manufactured airplanes that dropped a lot of high-quality bombs made right here in America by women in large factories.
> 
> This created a demand for electrical work to rebuild the stuff that America, her allies, and the Axis powers decided to do demolishion work on. The problem that the Euros had was too many unemployed engineers and too little money (the Euros used large portions of their gold reserves to buy American dollars, increasing the gold held in American banks to about 50% of all mined gold at the time). The IEC devices were made to be as cheap and weak as possible while still being able to do the job. It took an engineer to size the exact device for the task, making selection unnecessarily complicated, and since they weren't supposed to be repairable it also meant a new device had to be manufactured for every failed device providing an ongoing market for IEC devices.
> 
> I'm not trying to start an argument. I'm just trying to explain why I believe things are different.


Could you go into more detail on you thoughts?


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## uconduit (Jun 6, 2012)

HARRY304E said:


> Could you go into more detail on you thoughts?


NEMA: an investment in America, quality, durable, repairable
IEC: bean counter-approved, built-in obsolescence


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## HARRY304E (Sep 15, 2010)

uconduit said:


> NEMA: an investment in America, quality, durable, repairable
> IEC: bean counter-approved, built-in obsolescence


That seems to be the case with everything built these days....:no:


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