is primarily used to set the backlash acceleration amount in specific control series like the Fanuc 15i . In other common series (such as 16i, 18i, and 21i), this function is often mapped to parameter 2048 instead. Key Details for Parameter 1860 (Backlash Acceleration)

To set parameter 1860, you typically need to:

Parameter 1860 (X) = 3000 mm/min

This appears if you enter a value outside the allowable range for your axis configuration. Check your machine's specific Fanuc manual.