Learning targets The participant should ... ... Understand the difference between absolute and symbolic addressing ... Understand the difference between local and global symbols ... Be able to watch global symbols in the PLC tag table ... Be able to edit a global symbol table
PLC tags / local tags PLC tags Local tags Scope of validity • Validthroughout the complete CPU • Only valid within the block in • Can be used by all blocks which they have been defined • The designation is unique • The same designation can be within the CPU used in different blocks for different purposes. Application • PLC tags • Local tags - I/O signals - Block parameters - Bit memories - Static data of a block - Temporary data Location of • PLC tags table • Block interface definition Representation • PLC tags are presented in • Local tags are presented quotation marks preceded by # Example: "Max" Example: #Niels
+ Create PLC tags with group functions
Sort PLC tags With a mouse click in the first row of the "Name" column, the table is sorted according to name.
Monitor PLC tags Monitor allon / off
PLC tags: fault This address is already used by another tag The entered address does not correspond to the data type of the tag If the name already exists in the table, a "_1" is automatically appended.
Block editor: Symbol selection The selection of symbols offered is intelligently restricted after each letter is entered to the corresponding symbols of the PLC tag table and the local tags
Block editor:Rename individual tag The changes take immediate effect throughout the entire program.
Block editor:Rewire individual tag The changes take immediate effect throughout the entire program.
Exercise 5-1: Copy PLC tags for conveyor model from global library Drag and drop
Exercise 5-2: Complete PLC tags for conveyor model "Horn" (Q 8.7) "K_Conv_RIGHT" (Q 8.5) "K_Conv_LEFT" (Q 8.6) "Bay1" (I 8.5) "Bay2" (I 8.6) "Bay3" (I 8.7) "LB" (I8.0) "T_Bay1" (I 8.1) "T_Bay2" (I 8.2) "T_Bay3" (I 8.3) "T_Bay-LB" (I 8.4) "L_Bay1" (Q 8.1) "L_Bay2" (Q 8.2) "L_Bay3" (Q 8.3) "L_Bay-LB" (Q 8.4)