Can I Use STRING Parameters in the Application Logic?

No. STRING parameter data cannot be used as a primitive variable in Ladder or Structured Text application logic.

Some devices expose STRING data in their parameter table. These values usually represent text information. Depending on the parameter, the value may be editable or read-only.

However, this STRING data is handled as a structured parameter value, not as a primitive programming data type. Because of that, it cannot be used directly in the application logic and cannot be monitored as a regular programming variable.

Practical Impact

You can view or edit the STRING value when the device and parameter allow it, but you cannot use that value as a variable in Ladder or Structured Text logic.

If the application requires text-like identification, status information, or comparison logic, use supported programming data types and device-specific resources instead of relying on STRING parameters from the parameter table.