In the Fanuc ecosystem, parameters in the 9000+ range typically fall into two categories: Macro Program Protection:

Because these parameters control high-level machine options—such as the number of controlled axes, canned cycles, or memory capacity—they are typically locked by the manufacturer to prevent accidental changes that could "paralyse" the machine. Core Functionality

If you are looking at a parameter screen and seeing numbers like "1", "0", "50.000", these are likely variable values used by the machine builder's macro programs to store tool offsets, fixture offsets, or machine states (e.g., "Tool Change Arm Position").

Changing parameters—especially in the 9000 range—without proper documentation or a backup can lock you out of the control, disable critical functions, or cause the machine to behave unpredictably. Always write down the original values before making changes.