Fanuc Parameter 8901 Better Guide

Many shops use a “Reference Tool” or “Master Tool” to set the entire work coordinate system (G54). Setting 8901 = 1 allows you to shift the entire work offset (e.g., G54 Z) without corrupting individual tool geometry offsets. This is a massive time-saver when a casting or forging changes dimension mid-run.

Better is not a universal number. It is: fanuc parameter 8901 better

Always test with an air cut and a thread go/no-go gauge after changing. And remember: Parameter 8901 is write-protected (requires PWE = 1) and often requires a power cycle to take effect. Many shops use a “Reference Tool” or “Master

If you truly want the best behavior, combine 8901 with Parameter 4000#2 = 1 (high-speed rigid tapping mode) on 31i-B5 controls. Always test with an air cut and a

Final note: “Better” without diagnostics is guesswork. Use FANUC’s Servo Guide or look at Diagnosis 300 (synchronous error) before and after changing 8901. The goal is minimum following error difference between spindle and axis—that is the true measure of “better.”

A: Check Parameter 1401 (bit 6). Your machine may lack the "AICC II" option. Fanuc sells this as a paid software option (DNC operation or High-speed machining package). If you haven't purchased the option, the machine will alarm. You cannot "hack" 8901=2 without the license.

“Better” also requires: