IEC vs. Traditional

Discussion in 'General Electronics Chat' started by VoodooMojo, Apr 18, 2010.

  1. VoodooMojo

    Thread Starter Active Member

    Nov 28, 2009
    I have been tapped on the shoulder by higher-ups to set up a training package for safety circuits on a few different models we manufacture.
    The equipment is distributed across the entire planet and outward.

    This forum is a snapshot from around the world and your input is important to me.

    A simple question.

    What do we prefer and what is the norm in your thinking when it comes to logic gate symbols. Traditional or IEC?

    If you were a technician following complex logic diagrams, which are you more comfortable with.

    Would it be worth my while to do both?
  2. Wendy


    Mar 24, 2008
    Depends on what the product is. If it is traditional electronics then logic gates are the way to go.

    Many industrial applications use ladder diagrams, because of the number of relays, this is still digital.

    What is the typical education of the techs your training? If it is anything electronic then the gates are going to be common.

    A side note, I've never seen the IEC symbols in my life. In what context are they taught?

    My 2¢
  3. beenthere

    Retired Moderator

    Apr 20, 2004
    I got into logic at a time when the symbols were simply circles (bubble logic). The Mil-Std. 806 symbols were really great as a replacement, as you could see the basic functions just from the shape.

    The IEC standard is consistent and actually better organized, but the lack of obvious function until the box is examined makes it harder for me to run through a chain of logic.
  4. studiot

    AAC Fanatic!

    Nov 9, 2007
    Several times in the history of electrical / electronic engineering there has been a parting of the ways between

    'them as do and them as pontificate'

    By the latter I mean the standards organisations which have tried to impose.

    Each time progress by the former has left the latter stranded at first base.

    Simple test: what symbols do your drawing packages offer?
    Why do you think that is?

    Another test:
    What symbols were used in 1930; 1950; 1980 and are still in use in 2010?
    If you look back at the standards for those times it is amazing how quaint some seem.
  5. SgtWookie


    Jul 17, 2007
    I prefer the standard (conventional) over the IEC symbols.

    I haven't seen any schematics using IEC format in a while.

    The conventional symbols require much less effort to interpret than the IEC symbols, as it is shape recognition rather than reading/interpreting a formula.
  6. VoodooMojo

    Thread Starter Active Member

    Nov 28, 2009
    to answer Bill, the techs are electronics trained and or degreed. They will probably have no issue either way. It's just my concern over the hours I will be devoting to this project. If I have to do the mapping both ways then it will be to my benefit for I will become familiar with IEC symbols. I just don't want or need to burden my brain with things that I don't need or use.

    When I "volunteered" for this project I thought it was a slam-dunk.
    Then I was asked what symbols I would use. I knew the IEC symbols existed but never used them or had reason to need to use them.

    At the time (years and years ago) I found that redrawing the logic symbols (bubble logic) as relays would help me follow the logic trail. I got used to the MIL-806 symbols very easily.

    It will not be the slam-dunk if I have to use the IEC symbols.
    I also find it a bit tedious following the logic chain with them.
    I am hoping that the IEC symbols are so unused that it will not be required.

    The board pictured here is the main controller board used on thousands of units for the last 11 years or so.
    It is old technology now and not long to be supported by the manufacturer (Sauer Danfoss).

    My mission is to show the logic trail from the black plugs at the top right (from limit switches, rotary sensors, inclinometers, angle sensors etc) through the many logic gates (HC574, HC14, etc) clustered on the top left (second) quadrant, to the microcontroller (SAF-C167CR-LM) at left center. Then the easy path out through the white plugs via the high-side power switches (BTS621s and BTS650s.

    I have it nearly finished using the traditional symbols.
    I dread having to redo it with IEC.

    we all have a cross to bear.

    Thanks for the responses.
    Fingers crossed, traditional is all I will need.
  7. rjenkins

    AAC Fanatic!

    Nov 6, 2005
    I'd also say stick to the traditional sybols, they are most used and easier to read at a glance.

    But, do a simple IEC vs traditional 'cheat sheet' to hand out so your trainees have been formally provided with that info in case it's required at some future point.

    ps. Just looked at the pics - I see you are also a Toughbook fan.. (This is written on a CF-29).
  8. Bychon


    Mar 12, 2010
    I also vote for tradidional because they are so much quicker to read. I have said to people, "I can read a schematic faster than I can read English" (and I have lived in the U.S all my life). Using IEC symbols requires me to stop and read English. Not an improvement.

    I think the "cheat sheet" idea is also good. It covers the required territory without complicating the drawings.
  9. retched

    AAC Fanatic!

    Dec 5, 2009
    You have a JOB?


    Stick with traditional. Anyone that has been schooled in the last 90 years have learned logic in that form. It is unlikely that IEC will catch on until it is the only form taught and all of us have died off. If your next generation design has less than 50 year viability, you are safe.

    As rjenkins and Bychon said, you can include the sheet you attached in post 1 as an addendum or appendix to your report so if someone digs it up in 500 years, they can back convert.
    Last edited: Apr 18, 2010
  10. VoodooMojo

    Thread Starter Active Member

    Nov 28, 2009
    ps. Just looked at the pics - I see you are also a Toughbook fan.. (This is written on a CF-29).
    Robert Jenkins.

    not to sound like a Panasonic commercial, but I have been using the cf-29 since late 2004. I used to use Toshiba's but had to replace on the average 2 a year from dropping from a height or getting rained on. The toughbook has fallen from many a perilous height. Any lap-top used in the field by me for a period of over 5 years has to be tough.

    and whew am I glad the consensus is for the traditional.
    I was a bit concerned that new graduates from EE studies would give me the bad news that they were only being taught IEC at the university.

    My mind flows freely with the traditional and rarely do I have to think twice following the logic flow.
    Translating to IEC I will have to use the cheat sheet myself just to draw up a circuit.

    Thanks again for the input.