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21 Oct 15: Applications 23: Control Systems--Ladder Diagrams

Maybe it is time to do away with Ladder Diagrams

Back when I started working in industry, we made "ladder diagrams" for electrical control.  That is long enough ago that ladder diagrams were necessary--the machinery had large control panels full of discrete components hard wired together.

When PLCs and then DCS came along, ladder diagrams stayed.  The reason was control logic designers were used to doing ladder diagrams and hence that method of conveying information continued.

Now, forty years later, we still have ladder diagrams. My personal view is that it is long past time to eliminate these now confusing documents from the information flow.  We need a better, more efficient, more streamlined way to get from P & IDs to lines of programming in the DCS.

This is a subject which I don't touch every day, so I would like to hear your thoughts.  Is it time for ladder logic to go or am I missing something?
We would like to hear from you. Please send an email to [email protected] 
with "LGMI Frontiers" in the subject line. 

As always, your comments will be appreciated.
Think light!


Brian Brogdon, Ph.D.
Executive Director




Jim Thompson

Send us your comments by emailing Brian Brogdon
or Jim Thompson!




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