Fanuc Parameter 8901 Better < Firefox >

In the world of FANUC CNC controls (Series 0i, 30i, 31i, 35i, etc.), Parameter 8901 is a small but mighty binary switch. Officially titled "Rigid Tapping: Axis Selection for Synchronization Error Detection," its default setting works for 80% of users. But "better" is not a single setting—it is a strategy.

To achieve a better result with Parameter 8901, you must understand its two bits and then apply the correct logic for your machine’s mechanical configuration. fanuc parameter 8901 better

The definition of a "better" setting depends entirely on the application (Roughing vs. Finishing). In the world of FANUC CNC controls (Series

Traditional reference return uses a deceleration dog (a physical limit switch) followed by the first grid pulse from the encoder. Over time, dogs can wear, shift, or get dirty. Also, on high-speed machines, dog bounce can cause inconsistent reference positions by 1–2 encoder lines. The “better” setting typically refers to bit 0 (8901

Parameter 8901, when set optimally, allows:

The “better” setting typically refers to bit 0 (8901.0) = 1 for most modern setups.