Publication 1756-PM004C-EN-P - October 2009 27
Organize Tags Chapter 2
Data Type
The following table outlines the most common data types and when to use
each.
Term Definition
Data type The data type defines the type of data that a tag stores, such as a bit,
integer, floating-point value, string, and so forth.
Structure A data type that is a combination of other data types.
• A structure is formatted to create a unique data type that matches a
specific need.
• Within a structure, each individual data type is called a member.
• Like tags, members have a name and data type.
• A Logix5000 controller contains a set of predefined structures (data
types) for use with specific instructions such as timers, counters,
Function Blocks, and so forth.
• You can create your own structures, called a user-defined data type.
For Select
Analog device in floating-point mode REAL
Analog device in integer mode (for very fast sample rates) INT
ASCII characters String
Bit BOOL
Counter COUNTER
Digital I/O point BOOL
Floating-point number REAL
Integer (whole number) DINT
Sequencer CONTROL
Timer TIMER