Most manufacturers set this between 20 and 100 (
It is critical to understand that Parameter 1860 is not a "global constant" across every single FANUC firmware version. Depending on your specific model and the options installed, the function of 1860 shifts slightly.
value used to adjust the zero point after a reference return. Maintenance & Troubleshooting Read-Only Nature fanuc parameter 1860 full
Be careful not to set a value larger than the (the distance between two encoder "grid" pulses). If the shift is too large, the machine might skip a grid and home to the wrong position entirely.
| Method | When to Use | Risk Level | | :--- | :--- | :--- | | | After replacing a limit switch or deceleration dog. | Medium | | Reference Position Shift (1860) | After replacing absolute encoder or battery. | High | | Work Shift (G54-G59) | Daily part setup. No permanent machine change. | Low | | External Offset | Temporary tool length changes. | Low | Most manufacturers set this between 20 and 100
A "full" shift in one direction would be entering 99999999 , which would shift zero approximately 99,999 mm (99 meters) – obviously not practical. The practical full range is limited by your machine's physical travel. Never exceed the hard limit switches.
In the vast ecosystem of FANUC CNC parameters, certain numbers are famous for simple functions like handwheel feed rates (No. 1430), while others are infamous for their mystery. Parameter 1860 belongs firmly in the second category. Search any FANUC forum, and you will find a trail of confused engineers wondering why their machine lost zero, what the difference is between 1860 and 1861, or why a "Backlash Acceleration" setting is suddenly breaking their rotary axis alignment. | Medium | | Reference Position Shift (1860)
is a critical axis-specific setting used to store and display the current position data of an absolute position detector (encoder). Parameter Definition Parameter Number : Absolute position detector current position data. : 4-word (integer).
: When a new absolute pulse coder is installed.