Object Ladder - YOKOGAWA Revolution FA-M3 R Technical Information

P L C
P L C
The FA-M3 Programming Tool WideField is a revolutionary application for programming object
ladder succeeding to structured ladder programming and created with new concept.
An object ladder is a new concept of developing programs. The object in which a piece of program
and the related devices are assembled for each functional unit called a block. The blocks are then
assembled together to form the entire ladder program. Each block can thus be functionally
independent, which improves productivity and program maintainability compared to structured
programming*.
An object ladder is highly reusable. When customizing an existing machine control program for a
particular user, the details of each block need not be checked; blocks are simply added or replaced.
Conventional ladder
programming
TI 34M6A01-01E

Object Ladder

1990
Structured
programming
2000
Object ladder
programming
*Structured programming. A programming method proposed by
Yokogawa Electric Corporation in 1989, in which an increasingly
complexed ladder program is divided into parts for individual functional
units so that developers can easily understand the program framework,
and improved productivity and program maintainability. As these
advantages became recognized in the 1990's, structured programming
grew rapidly. Other PLC manufacturers rolled out products based on the
same concept, and structured programming is now the de facto standard
in PLCs.
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