Jump to content


Photo
- - - - -

PLC Beginner


  • Please log in to reply
8 replies to this topic

#1 Dan Col

Dan Col

    Newbie

  • MrPLC Member
  • PipPip
  • 8 posts
  • Country:United Kingdom
    United Kingdom

Posted 19 June 2011 - 11:44 AM

Hi all,

I figure this is the best forum that i can choose to ask for help with starting out with PLC's. I am 23 years old and have for the past 3years been designing control panels and systems which at times incoporated PLC's. I have now started to programme them, which has mainly comprised of Mitsubishi FX Series type PLC's. Lately i have written programmes for the new Siemens Logo! intel relays. What i find sometimes is that when i have been asked to write programmes for systems that i never seem to know where to start and when i do i question whether i am starting the programmes correctly. Is there a structure that anyone sticks too? I realise that its not so much a big deal with certain programmes but I want to create a check list of things that i can tick off and know i haven't over looked anything. I do admit to getting kind of nervous when i am the last person on a project and if the system doesnt work then it points to me, i will overcome these nerves in time and when a little more experience comes my way.

I just want to know the basics to automation and plc's and i believe if i know this then i can build upon this and look into becoming the best plc programmer that i possibly can be. I tend to aim high and so if anyone can pass on some information to me reading material, general advice, etc? that would be very much appreciated.

Thank you for your time

Dan
------------------------------------------------------------------------------------------------
"Chase it!"

#2 Crossbow

Crossbow

    Automation Engineer

  • MrPLC Admin
  • 3684 posts
  • Gender:Male
  • Location:Edge of Insanity
  • Country:United States
    United States

Posted 19 June 2011 - 05:09 PM

Most PLC vendors (including Mitsubishi and Siemens) have some basic tutorials of their software on their websites. I know Mitsubishi has several computer based training packages. Siemens has their Step 2000 training which is also free. That's one place to start.

And you will learn more going to an instructor-led training, which you can also get from most vendors or their distributors.

#3 gleblanc

gleblanc

    Production Specialist

  • MrPLC Member
  • PipPipPip
  • 137 posts
  • Gender:Male
  • Location:Williamstown, WV
  • Country:United States
    United States

Posted 22 June 2011 - 05:20 AM

Hi all,

I figure this is the best forum that i can choose to ask for help with starting out with PLC's. I am 23 years old and have for the past 3years been designing control panels and systems which at times incoporated PLC's. I have now started to programme them, which has mainly comprised of Mitsubishi FX Series type PLC's. Lately i have written programmes for the new Siemens Logo! intel relays. What i find sometimes is that when i have been asked to write programmes for systems that i never seem to know where to start and when i do i question whether i am starting the programmes correctly. Is there a structure that anyone sticks too? I realise that its not so much a big deal with certain programmes but I want to create a check list of things that i can tick off and know i haven't over looked anything. I do admit to getting kind of nervous when i am the last person on a project and if the system doesnt work then it points to me, i will overcome these nerves in time and when a little more experience comes my way.

I just want to know the basics to automation and plc's and i believe if i know this then i can build upon this and look into becoming the best plc programmer that i possibly can be. I tend to aim high and so if anyone can pass on some information to me reading material, general advice, etc? that would be very much appreciated.

Thank you for your time

Dan


I think Paulengr has written on this a couple of times in the past, have you searched the archives already? The most important step when programming PLCs is to know what you're going to write before you actually start writing. A detailed plan for the design of the program and an I/O list are a good start. Most of the machines I design end up using some sort of state machine to help keep track of what is going on, and what should be happening. I think the folks who design machines for continuous processes tend to use a different design, but having that design written down on paper is a big help. Looks like I even have one of Paul's threads bookmarked.

Learning to program great

Come back and ask more questions after you read that thread. Paul says everything I could, only he says it better.

#4 Dan Col

Dan Col

    Newbie

  • MrPLC Member
  • PipPip
  • 8 posts
  • Country:United Kingdom
    United Kingdom

Posted 27 June 2011 - 04:44 PM


Hi all,

I figure this is the best forum that i can choose to ask for help with starting out with PLC's. I am 23 years old and have for the past 3years been designing control panels and systems which at times incoporated PLC's. I have now started to programme them, which has mainly comprised of Mitsubishi FX Series type PLC's. Lately i have written programmes for the new Siemens Logo! intel relays. What i find sometimes is that when i have been asked to write programmes for systems that i never seem to know where to start and when i do i question whether i am starting the programmes correctly. Is there a structure that anyone sticks too? I realise that its not so much a big deal with certain programmes but I want to create a check list of things that i can tick off and know i haven't over looked anything. I do admit to getting kind of nervous when i am the last person on a project and if the system doesnt work then it points to me, i will overcome these nerves in time and when a little more experience comes my way.

I just want to know the basics to automation and plc's and i believe if i know this then i can build upon this and look into becoming the best plc programmer that i possibly can be. I tend to aim high and so if anyone can pass on some information to me reading material, general advice, etc? that would be very much appreciated.

Thank you for your time

Dan


I think Paulengr has written on this a couple of times in the past, have you searched the archives already? The most important step when programming PLCs is to know what you're going to write before you actually start writing. A detailed plan for the design of the program and an I/O list are a good start. Most of the machines I design end up using some sort of state machine to help keep track of what is going on, and what should be happening. I think the folks who design machines for continuous processes tend to use a different design, but having that design written down on paper is a big help. Looks like I even have one of Paul's threads bookmarked.

Learning to program great

Come back and ask more questions after you read that thread. Paul says everything I could, only he says it better.




Thank you for getting back to me with these answers, i will take a look at that link tomorrow at work as i have a little program that I have to start then so hopefully i can use this to my advantage.

Thank you
------------------------------------------------------------------------------------------------
"Chase it!"

#5 BobB

BobB

    BobB

  • MrPLC Member
  • PipPipPipPipPipPip
  • 1659 posts
  • Location:Sydney Australia
  • Interests:Omron, gardening, single malt scotch (with crushed ice only) car racing, music (most kinds [no C&W please]).
  • Country:Australia
    Australia

Posted 29 June 2011 - 04:43 AM

It is very hard to get started. The problem is that you can only obtain basic training on what functions etc are in a PLC and some useful applications.
Experience and/or working with a good, experienced programmer is really the best bet. Hard to come by unfortunately.
One piece of advice I would present to you is think outside the square.
One other absolute essential is a really good working/design/troubleshooting knowledge of control systems - that is always from experience, falling on your tail, repairing machinery with no knowledge of the machine and no drawings.
Did that for years - 3 days later sorted it out.
I am completely self taught and have learned from being thrown into situations I know nothing about, stupid deadlines, arriving onsite with half the wiring done and being expected to commission a system.
When your boss tells you how a system is to be designed, how it is to run, what the client requires and then you fly 5000 ks with a pile of rubbish that is useless then it gets interesting.
Have to start again, everyone else is ready, you of course are not due to the criteria given to you by your boss.
The last time this happened I spent 17 weeks on an island in the Indian Ocean completely re-writing and re-developing an automatic power station control system.
Not only 17 PLCs but also a SCADA system with 5500 tags - and I was on my own.
Mr Glenfiddich got a hiding for the 17 weeks but I would not have been able to do it if I did not think outside the square.
Standard type system are really fairly easy but I have only found about 4 'standard' systems in the 5-600 systems I have programmed over the years. And then there are communications to other devices - get ready to learn magic.
Good luck in your endeavours.
The Old Pfhaart

Posted Image

#6 Andy_P

Andy_P

    Sparky

  • MrPLC Member
  • PipPipPip
  • 405 posts
  • Gender:Male
  • Location:Melbourne
  • Country:Australia
    Australia

Posted 02 July 2011 - 08:29 AM

Bob, I feel your pain mate!

To the OP, I will echo what Bob has said.

Be prepared to:

  • Dive into manuals.
  • Answer questions like "Can't you just program it out?" when trying to sort out a breakdown with half the site management hopping about behind you. (Offer them a chair, I have found that gets rid of them.)
  • Remember that it may not be solely yourself who has to read your program. It may need to be interrogated by others, such as site maintenance, who will possibly not be as knowledgeable. Keep it clear and well commented. I used to be on this side of the fence, and I can tell you that it is no fun working a night shift being faced by some incomprehensible program at 3am.
  • Do not be afraid to experiment. If a piece of code works, it is not wrong. However, it may be possible to make it work better or more efficiently.
  • Organise your I/O and memory. For example, if you have 6 stages of a process that have 6 solenoids, assign them to outputs O0.1 through O0.6 if possible, but at least consecutive. This will help in the long run with documentation but also with more complex constructs like indirect addressing.

Good luck!


#7 RafaelMankilla

RafaelMankilla

    Newbie

  • MrPLC Member
  • PipPip
  • 7 posts
  • Country:United States
    United States

Posted 27 July 2011 - 04:56 PM

Hi all,

I figure this is the best forum that i can choose to ask for help with starting out with PLC's. I am 23 years old and have for the past 3years been designing control panels and systems which at times incoporated PLC's. I have now started to programme them, which has mainly comprised of Mitsubishi FX Series type PLC's. Lately i have written programmes for the new Siemens Logo! intel relays. What i find sometimes is that when i have been asked to write programmes for systems that i never seem to know where to start and when i do i question whether i am starting the programmes correctly. Is there a structure that anyone sticks too? I realise that its not so much a big deal with certain programmes but I want to create a check list of things that i can tick off and know i haven't over looked anything. I do admit to getting kind of nervous when i am the last person on a project and if the system doesnt work then it points to me, i will overcome these nerves in time and when a little more experience comes my way.

I just want to know the basics to automation and plc's and i believe if i know this then i can build upon this and look into becoming the best plc programmer that i possibly can be. I tend to aim high and so if anyone can pass on some information to me reading material, general advice, etc? that would be very much appreciated.

Thank you for your time

Dan


I am fairly new to the HMI and PLC scene as well but i find that the more i read on the specific controller or component that i am trying to use the better of i am. I know this can be a pain but like someone else responded to you "Be prepared to dive into manuals". Good luck and maybe you would like to check out HMI/PLC Combo's. I have posted a link to the HMI's that i currently work with.
www.operatorinterface.org
Thanks
Ralph

Edited by RafaelMankilla, 27 July 2011 - 04:56 PM.


#8 BobB

BobB

    BobB

  • MrPLC Member
  • PipPipPipPipPipPip
  • 1659 posts
  • Location:Sydney Australia
  • Interests:Omron, gardening, single malt scotch (with crushed ice only) car racing, music (most kinds [no C&W please]).
  • Country:Australia
    Australia

Posted 28 July 2011 - 01:17 AM

Old saying - 'when all else fails read the manual'.
The Old Pfhaart

Posted Image

#9 RussB

RussB

    Sparky

  • MrPLC Member
  • PipPipPip
  • 487 posts
  • Gender:Male
  • Location:West MI
  • Country:United States
    United States

Posted 28 July 2011 - 08:21 AM

Keep It Simple.
- Start by outlining a simple Sequence of Operations on paper.
- Write the logic to control the process, leaving out any and all diagnostics.
- Make notes on needed/wanted diagnostics in your paper outline, nothing fancy.
- If possible simulate the control sequence for verification.
- Begin adding the diagnostics, put these in a separate Block or subroutine if possible, this keeps the 'control' simple. Of course some of these will need to interact with the control blocks.
Of course there are hundreds of other valid ways to begin.
HTH
Russ <))>(
LEARN something today so you can TEACH something tomorrow.
DETAIL in your question, promotes DETAIL in my answer.
Do you "Believe"? Do you vote? Please Read:

#10 DannyMan

DannyMan

    Hi, I am New!

  • MrPLC Member
  • Pip
  • 4 posts
  • Gender:Male
  • Location:California USA
  • Country:United States
    United States

Posted 29 July 2011 - 07:37 PM

Luckily all ladder programming builds on the same basics so actually you can simply find a cheap used PLC of any model on ebay and start practicing and make your own checklist.
USB to Serial adapter units and other data stuff...




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users