Fanuc | Parameter 1860 Full |top|

Ensure the machine is entirely clear of tools, workpieces, and fixtures.

Put the machine in MDI Mode . Go to the SETTING page and set PARAMETER WRITE (PWE) to 1 . (Note: This will trigger a P/S 100 alarm, which is normal).

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.

Fanuc Parameter 1860 stores the absolute encoder pulse count for each axis, which is crucial for resolving 300 APC alarms caused by lost positional data, often due to dead batteries. Fixing the alarm involves replacing the batteries, setting Parameter 1815 (bit 4) to 1, and re-establishing the physical home position to automatically update Parameter 1860. For detailed instructions, you can read the Practical Machinist discussion and CNCmakers technical support . CNC Fanuc Resetting home position After switching batteries fanuc parameter 1860 full

In Fanuc CNC systems, is specifically used to define the current position (or absolute position) of each axis when using an absolute pulse coder. Function of Parameter 1860

To manage Parameter 1860 successfully:

On vertical axes (like the Z-axis), a built-in mechanical brake keeps the axis from falling when power is removed. If this brake drags or fails to release fully when the axis moves, it creates immense friction during rapid traverse, causing an excess error alarm. 3. Low Servo Amplifier Voltage or Failing Drive Ensure the machine is entirely clear of tools,

In CNC machining, maintaining accurate position tracking on rotary axes (

Before adjusting Parameter 1860 for gear ratio issues:

Configuration, Function, and Troubleshooting of Parameter 1860 Applicable Systems: FANUC Series 16i, 18i, 21i, 30i, 31i, 32i, 0i-TD/TF, 0i-MD/MF Category: Servo Initialization / Axis Setting (Note: This will trigger a P/S 100 alarm, which is normal)

References: Fanuc 0i-D, 0i-F, 31i-B5 Series Connection Manual (B-64643EN) and Parameter Manual (B-64640EN). Always consult your specific machine tool builder's documentation as they may override standard Fanuc recommendations with custom PMC logic or secondary parameters.

Without this setting, a machine might display a position of 720° after two full revolutions. With parameter 1860 set, the CNC rounds the coordinate, showing the position relative to the 360-degree circle (e.g., 720° becomes 0° or 360° depending on configuration). Key Related Parameters

Parameter 1821 (Reference Counter Size) must always match or cleanly divide into the feedback resolution cycle defined by Parameter 1860. If they do not align, the machine will fail to establish a repeatable home position.