What role does the "G90" command serve in FANUC CNC systems?

The "G90" command in FANUC CNC systems is used to set the machine to absolute positioning mode. In this mode, all coordinate values provided in a program refer to a fixed origin point, allowing for precise and controlled movement throughout the machining process. When using absolute coordinates, the machine interprets the provided positions in relation to the established zero point, ensuring accuracy in machining operations.

By utilizing absolute positioning, operators can effectively plan and execute complex machining tasks, as it simplifies the programming of movements to specific locations rather than making adjustments based on the last position – which would be the case if incremental positioning were used instead. This characteristic of G90 ensures that the CNC machine consistently follows predefined paths and makes it easier to understand the positioning of machining processes, which is crucial for quality control and precision manufacturing.