PLC Tutorial for Beginners - Creating & Using function blocks in Omron CJ series PLC

The OMRON FB Library is a collection of function block examples that aim to improve the
connectivity of the units for PLCs and FA components made by Omron. Here is a list of the
benefits to be gained from using the
OMRON FB Library:
(1) No need to create ladder diagrams using basic functions of the PLC units and FA
components
More time can be spent on bespoke programs for the external devices, rather than creating
basic ladder diagrams, as these are already available.
(2) Easy to use
A functioning program is achieved by loading the function block file to perform the target
functionality, then by inputting an instance (function block call statement) to the ladder
diagram program and setting addresses (parameters) for the inputs and outputs.
(3) Testing of program operation is unnecessary
Omron has tested the Function Block library. Debugging the programs for operating the unit
and FA components for the PLCs is unnecessary for the user.
(4) Easy to understand
The function block has a clearly displayed name for its body and instances. A fixed name can
be applied to the process.
The instance (function block call statement) has input and output parameters. As the
temporary relay and processing data is not displayed, the values of the inputs and outputs are
more visible.
Furthermore, as the modification of the parameters is localized, fine control during debugging
etc. is easier.
Finally, as the internal processing of the function block is not displayed when the instance is
used in the ladder diagram, the ladder diagram program looks simpler to the end-user.
(5) Extendibility in the future
Omron will not change the interface between the ladder diagram and the function blocks.
Units will operate by replacing the function block to the corresponding FB for the new unit in
the event of PLC and the FA component upgrades, for higher performance or enhancements,
in the future.