Fanuc Parameter 1860 Full ^new^ ★ Pro & Instant

Fanuc Parameter 1860 (Position of the absolute position detector) is a read-only parameter that displays the current position value from the absolute pulse coder. While it is not a setting you typically edit manually, it serves as a critical reference point for the CNC system to maintain axis alignment without needing to re-home after a power cycle. Key Characteristics and Function Data Type : 4-word (integer). Function : It tracks the absolute position of each axis. This value is automatically set and updated by the CNC when an axis is zeroed (specifically through Parameter 1815 APZ ). Usage : Maintenance technicians use this parameter to verify that the absolute pulse coder is correctly tracking the machine's physical position. Modular Arithmetic : The value may "wrap around" based on the encoder's count limits, which is normal behavior for absolute detectors. Related Reference Parameters When troubleshooting absolute position issues, you will likely need to check these associated parameters: Parameter 1815 : Used to set the absolute position reference (Bit 4: APZ). Parameter 1850 : Sets the grid shift amount to fine-tune the zero position. Parameter 1851 : Controls backlash compensation . Safety Note Do not attempt to force a value into Parameter 1860. On most systems, it is read-only . To change the machine's reference position, use the proper zero-point setting procedure involving Parameter 1815. Are you experiencing a specific alarm code or axis shift that led you to check this parameter? FANUC? M6 toolchange position. | Practical Machinist

Parameter 1860: Reference Point Return Speed (High-Speed "G28" Approach) 1. Overview

Function: Sets the rapid traverse rate (mm/min or inch/min) for the second stage of a reference point return operation (G28). Control Type: Used on FANUC Series 0i, 16i, 18i, 21i, 30i, 31i, 32i and similar models. Axis Association: Separate parameter per axis (e.g., 1860 for 1st axis, 1861 for 2nd axis, etc.). Units: Depends on the machine’s input increment system (metric: mm/min; inch: 0.1 inch/min).

2. Detailed Operation Context When you execute G28 X... Y... Z... , the reference point return occurs in two distinct phases : | Phase | Action | Speed Control | Parameter | |-------|--------|---------------|-----------| | 1 | Move from current position to an intermediate point (specified in G28 block) | G00 rapid rate | Parameter 1420 (Rapid traverse) | | 2 | Move from intermediate point to the machine reference point | Lower speed for final approach & deceleration | Parameter 1860 | fanuc parameter 1860 full

✅ Why separate speed? The second stage uses a slower speed to ensure the reference point is captured cleanly by the deceleration dog & position coder 1‑revolution signal — preventing overshoot or false reference return.

3. Parameter Structure

Data type: Real value (decimal allowed) Valid range: Fanuc Parameter 1860 (Position of the absolute position

Metric: 6 to 240,000 (mm/min) Inch: 6 to 96,000 (0.1 inch/min) — i.e., 0.6 to 9600 inch/min

Default value: 0 (meaning same as parameter 1420 – but this is not recommended for stability) Format example (1st axis): N1860 P1 (Axis 1) = 2000

4. Practical Setting Guidelines | Machine Type | Typical 1860 Value (mm/min) | Reason | |--------------|-----------------------------|--------| | Small milling | 500 – 2000 | Short deceleration zone, slower dog approach | | Large lathe | 2000 – 6000 | Heavy axis, needs consistent dog capture | | High-speed machining center | 1000 – 4000 | Balanced speed vs. repeatability | | Grinder | 200 – 1000 | Very fine reference accuracy required | Function : It tracks the absolute position of each axis

Rule of thumb: Set 1860 to approximately 10–30% of the axis rapid rate (1420). Example: If rapid = 20,000 mm/min → 1860 = 2000–6000 mm/min.

5. Effects of Incorrect Setting | Problem | Cause | |---------|-------| | Alarm PS0030 or PS0031 | 1860 set too high → reference point signal missed due to overshoot | | Inconsistent reference position (drift every cycle) | Speed too high for deceleration zone length (dog/switch timing mismatch) | | Long cycle time | 1860 set unnecessarily low (e.g., 100 mm/min on a large VMC) | | Machine overshoots reference point | 1860 > rapid rate (not allowed; parameter clamped internally) |