Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 34

■ When a conversion error occurs in VAR_INPUT, VAR_OUTPUT, or VAR_IN_OUT in a macro
type function block
A program block that is the calling source of the function block or the function block may cause the error. In this case, check
the inputs and outputs of the program block that is the calling source of the function block and the function block.
Ex.
A conversion error (1) occurs in VAR_OUTPUT in the macro type function block (FbPou)
If no error was found in (1), check the inputs and outputs (2) of the corresponding function block in the program block that is
the calling source.
Since the output variables of the function block have been passed to the write-protected label/device, a conversion error has
occurred in the above example.
3 PROGRAM ORGANIZATION UNITS
32
3.4 Precautions
(1)
(2)