I am an electrical engineer needing to know practical pics

Discussion in 'Career Advising' started by Bob Thomson, Sep 3, 2016.

  1. Bob Thomson

    Thread Starter New Member

    Sep 3, 2016
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    Have started a knew job where plcs rule, I need to know more about them and how to determine if fault is Plc or external?
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
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    First what is the type/make of PLC?
    So does it mean you have been thrown in the deep end with no experience of them?
    The beauty of the PLC is the onscreen ladder makes diagnosis relatively easy, compared to the old relay logic panels, there are books out there but it helps to zero in on the type used where you are working.'
    Max.
     
  3. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Assuming you know the basics of PLC functioning, I'd suggest getting hold of datasheets/manuals for specific PLCs and studying those in detail.
     
  4. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I see in the post title you mention PIC's ? Some use the same terminology for both PIC's and PLC's.
    Max.
     
  5. Bob Thomson

    Thread Starter New Member

    Sep 3, 2016
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    It's a Siemens used in a case erector
     
  6. Bob Thomson

    Thread Starter New Member

    Sep 3, 2016
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    Sorry just bad predictive
     
  7. Bob Thomson

    Thread Starter New Member

    Sep 3, 2016
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    Never worked with plcs ever
     
  8. MaxHeadRoom

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    The PLC has its basis in Boolean arithmetic, when writing a program, there is the basic rung method which simulates an electrical schematic system.
    As it was originally developed in N.A. it uses the same system of two vertical power rails, on the left and right hand sides with the logic progressing from left to right ending with the output function (or result) on the right hand side.
    Simulating the electrical schematic it replaces.
    After becoming familiar with this method, many PLC's have the ability to just use a form of straight boolean, and go back and forth between the two.
    I have not used the Siemens but I assume where you are there is a programming/diagnostic terminal that can usually be used off line and the ladder displayed on it, if so it should be possible to use it to do some familiarization off line.
    Also I would assume there should be programming manuals on hand to refer to.
    If you are at all familiar with the older relay logic/hard wired systems, it should not take too long to come up to speed.:cool:
    (Historical reference: GM and Dick Morley).
    Max.
     
  9. MaxHeadRoom

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    I must admit I had to Google 'Case Erector', worked on a few machines but had never heard of that one!
    Max.
     
  10. JoeJester

    AAC Fanatic!

    Apr 26, 2005
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  11. Bob Thomson

    Thread Starter New Member

    Sep 3, 2016
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    Thanks to all who replied, a big help.
     
  12. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    You might also want to have a look here:
    PLC Manual Basic Guide to PLCs

    This was found using the following query:
    PLC tutorial

    Bertus
     
  13. BR-549

    Well-Known Member

    Sep 22, 2013
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    Never worked with PLCs? Even with an electrical background, You have a lot of reading to do.
     
  14. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Just a little more on your question of trouble shooting, I assume these are M/C's purchased by the company, so you may not have the Siemens Ladder software for monitoring etc.
    This helps tremendously when trouble shooting as the whole PLC Pgm can be monitored in 'real time' otherwise without it, you are virtually limited to monitoring the I/O indicator LED's on the unit itself and this will only give you limited info.
    If it is not available, and down time of the machine is critical, it would pay to press for the aquasition of the software.
    Max.
     
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