Fanuc Parameter 1860 Full |link| May 2026

Understanding Fanuc Parameter 1860: Absolute Position Detection

Alarm PS 224 (Illegal parameter)

This appears if you enter a value outside the allowable range for your axis configuration. Check your machine's specific Fanuc manual. fanuc parameter 1860 full

Mechanical Overhaul: If you disconnect the motor from the ball screw, the physical relationship between the encoder and the machine zero changes. Cutting feedrate (F) = 3000 mm/min = 50

On a Fanuc CNC system, Parameter 1860 (also known as GRIDX) is a critical axis-specific setting used to define the grid shift amount for the reference position (home position). If you are getting a Stop Excess Error

In practice, for direct drive systems: $$ 1860 = \textReference Counter (1821) \div \textScrew Pitch (in pulses) $$ (Note: This varies heavily depending on whether the machine uses a Decimal Input method or the older Integer Input method.)

1. Replacing a Dead Battery or Absolute Encoder

If the absolute encoder battery dies, the machine loses its zero position. After replacing the battery, you must re-establish machine zero. Parameter 1860 allows you to "tell" the control where the new zero is relative to the mechanical hard stops.

• Cutting feedrate (F) = 3000 mm/min = 50 mm/sec
• Desired acceleration = 0.5 G ≈ 4905 mm/s² (moderate for a small VMC)
• Solve for T: T = Vc / a = 50 / 4905 ≈ 0.0102 seconds = 10.2 ms

If you are getting a Stop Excess Error and your Parameter 1860 is set to a standard value, the problem is likely mechanical or electrical, not the parameter itself: