Glossary · Automation fundamentals, platforms and components
INT (data type)
Also known as: Integer, 16-bit integer
German: INT
In IEC 61131-3, INT is the elementary data type for a signed 16-bit integer with a value range of −32,768 to 32,767. Related types are SINT, DINT and LINT (8, 32 and 64 bits) and the unsigned UINT variants.
- Automation components
- Standards
In one sentence
INT is the IEC 61131-3 data type for a signed 16-bit integer, ranging from −32,768 to 32,767.
Example
A raw analog input value is read as INT, typically in a range such as 0 to 27,648 for 4 to 20 mA on some controller families, and then scaled to engineering units.
How it applies
- Engineering: Choosing the right integer type avoids overflow; a counter that exceeds 32,767 in an INT wraps around or causes an error. Use DINT for larger values.
- Integration: When data is exchanged with other systems, byte order and signedness must match, for example in Modbus registers.
- Documentation: Interface descriptions and parameter lists should state data type, range, unit and scaling for each value. Raw integer values without scaling information cannot be interpreted.
- Maintenance: Online monitoring displays may show INT values in decimal or hexadecimal; technicians should check the display format.
INT vs. REAL
INT holds whole numbers exactly. REAL holds floating-point numbers with fractional parts but limited precision. Scaling an INT to a REAL engineering value should be documented, including the scaling formula.