1. Introduction to ControlLogix Function Block

2. Function Block Programming
Relatively new PLC language
ControlLogix only Allen-Bradley PLC family to support function block
From IEC specifications

3. Uses of Function Block
Process control such as PID
Drive systems

4. Why Function Block? New instructions
Advanced function block instructions have instructions that would take many ladder rungs to create equivalent logic.
Function block has user-defined blocks.

5. Not all relay ladder logic instructions are available in function block.
A ControlLogix routine must be 100% the same programming language.

6. Function Block Components
Function block routine
Function blocks for instructions
Input and output references
Wire connectors
Dotted wire for bit data
Solid line for value data

7. Create a New Function Block Routine
Routine name
Description
if desired
Select
routine type

8. Function Block Routine
Continuous Task
Main Ladder Routine
Function Block Routine

9. Function Block Sheet Delete sheet Navigate between sheets Sheet number
New sheet
Sheet Name
Show / hide grid
Coordinates
Grid

10. Language Element Toolbar
Input reference
Output reference
Output wire connector
Input wire connector

11. Input Reference for Bit
Bit value
Input
Reference
Dotted lines identify
as bit or BOOL data

12. Input Reference for Values
Bit data
Tag value
Solid line signifies
the tag contains a value

13. Output Reference Output reference to tag Bit value
Dotted line signifies bit data

14. Wire Connectors (1 of 3)
Used to move function block diagram wire from one sheet to another
Output from one sheet is an input to the next sheet

15. Wire Connectors (2 of 3) Sheet One Output wire connector Sheet Two
Input wire
connector
Coordinates

16. Wire Connectors (3 of 3)
Coordinates refer ahead to the input wire connector on the next sheet or back to the output wire connector on the previous sheet.
2A1 refers to sheet 2 coordinates A1.
1C2 refers to sheet 1 coordinates C2.

17. Language Element Toolbar
Boolean AND
Boolean OR
Boolean Excusive OR
Boolean NOT
Up / Down counter
Timer on-delay with reset

18. Boolean AND

19. Relay Ladder AND Logic

20. Boolean OR

21. Relay Ladder OR Logic

22. Boolean Exclusive OR

23. Relay Ladder Logic Excusive OR

24. Boolean Not

25. Relay Ladder NOT Logic

26. Adding Address Tag

27. Drag Wire To Target
Drag wire to target. When target changes drop wire.

28. Function Block Properties
Click here to go to properties.

29. BAND Properties Box
Parameters visible?
Monitor values
Execution order