Parameter 1860 (often referred to as ) is a non-editable, read-only system value that represents the absolute position (encoder count) of a machine axis. This parameter is central to how a CNC system "remembers" its location without requiring a home return (homing) every time it is powered on. The Function of Parameter 1860
In Fanuc control systems, Parameter 1860 displays the current absolute position data received from the motor's pulse coder. Encoder Tracking
: It acts as a live digital readout of where the axis stands in relation to its established zero point. Automatic Synchronization : When an axis is zeroed using Parameter 1815 (APZ)
, the system captures the value in 1860 to establish the reference coordinate system. Diagnostic Use
: Since users cannot manually change this value, it is primarily used by technicians to verify if an encoder is losing counts or to troubleshoot axis "droop" or slippage during emergency stops. Practical Implications in Machine Operation
The "work" performed by Parameter 1860 is essential for maintaining precision in several scenarios: Absolute vs. Incremental
: Machines using absolute encoders rely on this parameter to bypass the need for a physical "dog-type" home switch. The control reads 1860 at startup to instantly know where the tool is. Axis Droop Monitoring
: On vertical axes (like the Z-axis) without counterweights, the spindle may drop slightly when the servos lose power (e.g., during an E-stop) before the mechanical brake engages. Technicians use Parameter 1860 to measure this displacement precisely, ensuring it doesn't exceed the machine's safety limits. System Integrity
: Because it uses modular arithmetic (the value "wraps around" once it reaches its maximum limit), it continuously tracks movement over the full travel of the axis without losing its place. Important Safety Note:
Never attempt to force-write or manipulate parameters in the 1800-series (Axis-related parameters) without referring to the official Fanuc Parameter Manual
for your specific control model (e.g., 0i, 16i, 18i), as incorrect settings can cause machine collisions. CNC Training Centre to reset your machine's zero position using these encoder counts? FANUC? M6 toolchange position. | Practical Machinist
Understanding Fanuc Parameter 1860: Reference Position and Absolute Encoders
Fanuc Parameter 1860 stores the absolute position of an axis within the current rotation of the encoder. It is a critical, read-only system parameter used by the CNC to track exactly where an axis is relative to its reference (home) position. If the value in Parameter 1860 is lost or incorrect—often due to a battery failure—the machine will lose its "sense" of where it is, leading to homing alarms. What is the Function of Parameter 1860?
In Fanuc CNC systems, Parameter 1860 acts as the machine's memory for axis position data when using absolute pulse coders (APC). Unlike incremental encoders, which must hit a "limit switch" or "dog" every time the machine starts up, absolute encoders always know their position.
Role in Homing: When an axis is successfully homed (set with Parameter 1815.4 APZ), the current encoder count is saved into Parameter 1860.
Data Type: It typically uses modular arithmetic, meaning the value "wraps around" based on the encoder's pulses per revolution.
Reference Completion: If the system detects a discrepancy between the physical position and the value in 1860, it may trigger a "Request for Reference Position Return". How Parameter 1860 Works During Startup
When you power on a Fanuc machine equipped with absolute encoders:
Verification: The CNC reads the current value from the encoder.
Comparison: It compares this value against the stored data in Parameter 1860.
Validation: If they match within a certain tolerance, the machine "remembers" its position immediately without requiring a manual zero return. Troubleshooting Common 1860 Issues
Most issues related to Parameter 1860 arise after a battery failure or motor replacement.
Alarms 300-349 (APC Alarms): These indicate that the absolute position data has been lost.
Reference Position Incomplete: If you reset Parameter 1815 but the machine doesn't move to the correct spot, the value in 1860 will often change automatically once a new reference point is established.
Soft Overtravel Alarms: If the stored position in 1860 suggests the machine is outside its travel limits upon startup, you may need to power on while holding "P" and "CAN" (Cancel) to bypass the check and re-home the axis. Step-by-Step: Setting the Reference Position
Because Parameter 1860 is a system-generated value, you do not "type in" a value manually. Instead, you perform a procedure to let the CNC update it:
Master the Fanuc Zero Return Procedure in 5 Steps - CNCFixtech
Fanuc parameter 1860 (also labeled as POSCNT) is a critical axis-specific setting used to define the position feedback pulse count for the spindle encoder. It essentially tells the CNC system how many pulses are generated for each revolution of the spindle, allowing for precise speed and position control. ⚙️ How Parameter 1860 Works
Feedback Link: It synchronizes the mechanical rotation of the spindle with the electrical pulses sent to the CNC.
Axis-Specific: Like many servo and spindle parameters, it is set individually for each axis or spindle defined in the system.
Scaling: It works in tandem with other gear ratio and detector parameters to ensure that if you command 1000 RPM, the machine accurately maintains exactly that speed. 🌟 Why It’s a "Good Feature"
This parameter is vital for high-precision operations that require the CNC to know the exact orientation of the spindle:
Rigid Tapping: Essential for syncing the feedrate of the Z-axis with the spindle's rotation to cut threads without a floating tap holder.
Spindle Orientation: Allows the machine to stop the spindle at a specific angle (e.g., for a tool change in an ATC).
Threading/Canned Cycles: Ensures the tool enters the part at the exact same angular position on every pass, which is necessary for multi-pass threading.
Speed Stability: Provides the feedback needed for the control to compensate for load changes, keeping the cutting speed constant. ⚠️ Pro-Tips for Setting fanuc parameter 1860 work
Backup First: Always back up your parameters before changing 1860, as an incorrect value can cause spindle alarms or "jittery" rotation.
PWE Mode: To edit it, you must be in MDI mode and have Parameter Write Enable (PWE) set to 1.
Consult Manuals: The exact value depends on your encoder's hardware (e.g., 1024, 4096, or 10000 pulses). Check your machine tool builder's documentation for the specific hardware rating.
If you're having trouble with a specific operation, let me know: Are you getting a spindle alarm? Is your rigid tapping failing or breaking taps? What model is your Fanuc control (e.g., 0i-MD, 31i)? PARAMETER MANUAL
Understanding FANUC Parameter 1860: Unlocking its Work and Applications
In the world of CNC machining, FANUC is a well-known and respected brand that provides high-performance control systems for a wide range of machine tools. One of the key features of FANUC controls is the use of parameters, which allow users to customize and optimize their machines for specific applications. In this article, we'll be focusing on FANUC parameter 1860 and its work, exploring what it does, how it works, and its practical applications.
What is FANUC Parameter 1860?
FANUC parameter 1860 is a specific setting within the FANUC control system that determines the scaling factor for the machine's position feedback. In essence, it adjusts the way the machine interprets position data from the feedback devices, such as encoders or resolvers. This parameter is usually used to fine-tune the machine's movement and positioning accuracy.
How Does FANUC Parameter 1860 Work?
When a FANUC control system is installed on a machine tool, it is typically set up with default parameters that provide a good starting point for most applications. However, to optimize the machine's performance, adjustments to these parameters may be necessary. Parameter 1860 comes into play when the machine's position feedback needs to be scaled.
The scaling factor set by parameter 1860 affects how the machine's control system interprets the position feedback data. A scaling factor of 1, for example, means that the machine will move exactly one unit (e.g., millimeter or inch) for every unit of feedback received. By adjusting this parameter, users can effectively change the machine's movement ratio, allowing for more precise control over the machining process.
Why is FANUC Parameter 1860 Important?
The correct setting of FANUC parameter 1860 is crucial for achieving accurate and precise machining results. Here are some reasons why:
Practical Applications of FANUC Parameter 1860
Here are some examples of how FANUC parameter 1860 is used in real-world applications:
How to Set FANUC Parameter 1860
Setting FANUC parameter 1860 requires a good understanding of the machine's mechanics, feedback devices, and the specific requirements of the application. Here are the general steps:
Conclusion
In conclusion, FANUC parameter 1860 plays a vital role in optimizing the performance of machine tools equipped with FANUC control systems. By understanding how this parameter works and its practical applications, users can unlock the full potential of their machines, achieving higher accuracy, precision, and productivity. Whether you're a CNC machining expert or a machine tool builder, knowledge of FANUC parameter 1860 is essential for delivering high-quality results.
Additional Tips and Best Practices
Here are some additional tips and best practices to keep in mind when working with FANUC parameter 1860:
By following these guidelines and best practices, users can ensure that their FANUC control system is optimized for maximum performance, accuracy, and productivity.
In the FANUC Series 30i, 31i, and 32i (as well as 16i, 18i, and 21i) CNC systems, Parameter 1860 (APZ) is a crucial bit-type parameter used to establish and indicate the Absolute Position for each axis when utilizing absolute pulse coders. Feature & Functionality
The primary feature of Parameter 1860 is to act as a status flag and setting for the Machine Zero (Home) Position. It works in conjunction with absolute encoders to ensure the machine knows its exact location without requiring a manual zero return every time it is powered on.
Establishing Reference Position: When setting up or "homing" a machine with absolute encoders, this parameter is changed from 0 to 1 to tell the CNC that the current physical position of the axis is the established reference (zero) point. Status Indication:
0: The reference position has not been established. The machine will usually display a "ZRN Needed" (Zero Return Needed) alarm.
1: The reference position is established. The control "remembers" this location even after power is cycled, provided the encoder battery remains healthy. Common Use Case: Grid Shift Adjustment
Parameter 1860 is most often used during maintenance or after a mechanical crash to reset the home position. A typical procedure involves: Moving the axis to the desired physical home position. Setting the APZ bit (Parameter 1860) to 0 for that axis. Powering the machine off and back on.
Setting the APZ bit back to 1 to lock in the new coordinate as the absolute zero. GE Fanuc Automation Series 30i/31i/32i Parameter Manual
Overview. This document serves as a comprehensive Parameter Manual for GE Fanuc Automation's advanced Computer Numerical Control (
Fanuc 21i-ta gridshift issues - CNC Machining - Practical Machinist
In the complex ecosystem of Fanuc CNC systems, Parameter 1860
serves as a critical configuration point for axis position detection
. While common maintenance often focuses on Parameter 1815 for setting the absolute zero position, Parameter 1860 specifically defines the Reference Position Offset (or shift) for each axis when using absolute pulse coders. The Role of Parameter 1860
Parameter 1860 functions as a digital bridge between the mechanical "Machine Zero" and the electrical "Grid Zero" detected by the absolute encoder. Grid Shift Mechanism Parameter 1860 (often referred to as ) is
: It is used to shift the reference position by a specific amount of pulses, allowing technicians to align the machine’s coordinate system without physically moving the limit switches or motor couplings. Absolute Position Data
: When an absolute encoder is enabled (via Parameter 1815#5), the system uses the value in 1860 to calculate the exact machine coordinate based on the position data stored during power-down. Operational Workflow
Setting or modifying Parameter 1860 typically occurs during machine commissioning or after a mechanical repair, such as a ballscrew replacement. Enabling Edits
: To change this value, the "Parameter Write Enable" (PWE) must be set to 1 in the Setting Screen Calculating the Shift
: Technicians determine the difference between the desired physical home position and the current absolute position reading. This difference is converted into "detection units" (pulses) and entered into 1860. Synchronization
: Once the value is entered, the axis typically requires a restart or a new "Zero Return" procedure to synchronize the encoder’s absolute data with the new offset. Technical Impact
Without a correctly configured Parameter 1860, the CNC system would lose its "memory" of where the tools and workpieces are located relative to the machine bed. This parameter ensures that even if the machine is turned off for extended periods, it resumes operation with high precision, maintaining the integrity of the work coordinate systems and preventing potential mechanical crashes.
In essence, Parameter 1860 is the "memory map" for an axis, ensuring that the physical reality of the machine matches its digital representation within the Fanuc control. step-by-step guide
on how to calculate the specific pulse value for your machine's axis? Series 16i-18i-MODEL B - Parameter Manual.pdf - Drivesul
Here’s a concise review for Fanuc Parameter 1860 related to “work” (typically workpiece handling or robotic hand control):
Review: Fanuc Parameter 1860 (Work / Hand Control)
⭐ 4.8/5 – Essential for end-of-arm tooling & workpiece management
Overview:
Parameter 1860 in Fanuc controls the hand number or workpiece handling configuration (often used in conjunction with hand control logic or work clamping). It’s critical for robots and machining centers that manage multiple grippers or part types.
Pros:
Cons:
Best for:
Tip: Always verify 1860’s value against your workpiece definition table (often param 1861–1865). Back up your PMC parameters before editing.
Would you like a sample ladder logic snippet or a safety checklist for changing this parameter?
Fanuc Parameter 1860 (often abbreviated as APZ) is used to indicate whether the zero point for an axis using an absolute pulse coder has been established. It is typically found on controls like the Fanuc 16/18/21 series and the 0i series. Function and Behavior
Purpose: This bit-type parameter identifies if the absolute position for a specific axis has been fixed.
Value "0": The zero point is not established. This usually occurs after replacing a battery (resulting in a "300 APC Alarm") or after a motor/encoder replacement.
Value "1": The absolute reference position is established. Once the zero-setting procedure is completed, the system automatically flips this bit from 0 to 1. Working with Parameter 1860
When the reference position is lost, you cannot simply change this parameter to "1" to fix it. You must physically move the machine and perform a zero-return procedure. Enable Parameter Write (PWE): Press the [SYSTEM] or [OFFSET/SETTING] key.
Find the [SETTING] soft key and set PARAMETER WRITE = 1. Note that this will trigger an alarm (typically alarm 100), which is normal. Zero-Setting Procedure: Manually jog the axis to its physical zero position.
In the parameter screen, locate Parameter 1815 (APZ bit) or 1860 (depending on the specific control model's logic). Set the relevant bit to "1" for the desired axis. Finalize:
Cycle the power to the machine to register the new absolute position.
Set PARAMETER WRITE back to 0 and clear any remaining alarms using [RESET]. Related Parameters
Parameter 1815: The primary parameter for Absolute Pulse Coder (APC) setup. Bit 4 (APZ) and Bit 5 (APC) are often configured alongside 1860.
Parameter 1851/1852: Used for Backlash Compensation once the axis is homed.
Parameter 1420: Controls the Rapid Traverse Rate for the axes after homing. How to Enable Parameter Write Enable (PWE) on a Fanuc CNC
In the world of FANUC CNC controls, Parameter 1860 serves a vital role in establishing and maintaining the machine's coordinate system. Specifically, it stores the current position of the absolute encoder for each axis in relation to the machine’s reference (home) point. 🛠️ What Parameter 1860 Does
On machines equipped with absolute encoders, Parameter 1860 acts as a "memory bank." It records the distance from the machine's zero point to the current absolute position. This allows the machine to "remember" exactly where it is, even after the power is turned off.
Axis-Specific: This is an axis-type parameter, meaning it has a unique value for X, Y, Z, and any additional axes.
Unit of Measure: Data is usually stored in detection units (the smallest increment the encoder can see), such as 0.001mm or 0.0001 inches.
Automatic Updates: Under normal operation, the control updates this value automatically as the axis moves. ⚠️ Common Scenarios & "Work" Involved Positioning accuracy : Incorrect scaling can lead to
You rarely need to touch Parameter 1860 manually unless there is a communication or hardware failure. "Work" involving this parameter typically occurs in these situations: 1. Battery Failure (APC Alarm)
If the backup battery for the Absolute Pulse Coder (APC) dies while the machine is off, the absolute position data is lost.
The Symptom: You'll see an "APC" or "300" series alarm (e.g., 300 APC Alarm: Axis Need ZRN).
The Fix: You must re-home the axis manually and toggle Parameter 1815 (APZ bit) to 1 to re-establish the reference, which then refreshes the value in Parameter 1860. 2. Motor or Encoder Replacement
When you swap out a servo motor or its encoder, the new unit won't have a record of the old machine zero.
The Work: Technicians must physically move the axis to its home position and "set" the absolute zero. This process re-synchronizes the physical position with the value stored in the control. 3. "Grid Shift" Adjustments
If your machine's zero point is slightly off (e.g., after a minor crash), you might adjust Parameter 1850 (Grid Shift).
The Result: Changing the grid shift effectively shifts how the control interprets the data in Parameter 1860, moving the machine's "Home" without moving the physical encoder marker. 💡 Pro-Tip: Safety First Before making any changes to the 1800-series parameters: Back up your parameters to a USB or CF card. Record the current values of 1815 and 1860 for all axes.
Ensure you are in MDI Mode with the Parameter Write Enable (PWE) set to 1.
If you are setting up a new axis:
Disclaimer: This guide is for educational purposes. Always consult the specific Fanuc Parameter Manual for your specific control model (Series 16i/18i/21i/30i/31i/32i) and contact your machine tool builder's service department before modifying system parameters.
Unlike static offsets, Parameter 1860 works dynamically: during a rigid tapping cycle, as the spindle reverses direction between hole bottom and retract, the CNC continuously applies the parameter 1860 adjustment to maintain synchronization. This ensures each thread is cut at the exact same helix angle, preventing "step" marks or oversized threads.
FANUC Parameter 1860 is a precise and powerful tool that bridges the digital command of the CNC with the analog reality of mechanical motion. While it may be overshadowed by more commonly discussed parameters, its correct configuration is the bedrock of accurate axis scaling, consistent homing, and safe operation. For any service engineer or machinist facing unexpected axis movement errors, verifying the value of Parameter 1860 against the specifications of the installed pulse coder is an essential diagnostic step. In the high-stakes world of precision machining, this single parameter ensures that a command to move one inch results in exactly one inch of movement—no more, no less.
Review: Understanding and Working with FANUC Parameter 1860
Introduction
FANUC is a leading manufacturer of CNC (Computer Numerical Control) systems, and their parameters play a crucial role in customizing and optimizing machine tool performance. Parameter 1860 is one such setting that holds significant importance in certain machining applications. This review aims to provide an in-depth understanding of FANUC parameter 1860, its functions, and how to work with it.
What is FANUC Parameter 1860?
Parameter 1860 is a specific setting in FANUC CNC systems that relates to the "Scaling function" or "Axis scaling" for a particular axis. It allows users to adjust the movement of a specific axis by scaling the command value. This parameter is especially useful in applications where the machine tool requires non-linear movement or where a specific axis needs to be adjusted to compensate for mechanical inaccuracies.
Functions of Parameter 1860
The primary function of parameter 1860 is to enable and set the scaling ratio for a specific axis. By adjusting this parameter, users can:
Working with Parameter 1860
To work with parameter 1860, follow these general steps:
Best Practices and Precautions
When working with parameter 1860, keep in mind:
Conclusion
FANUC parameter 1860 is a powerful tool for customizing and optimizing machine tool performance. By understanding its functions and following best practices, users can effectively utilize this parameter to achieve specific machining requirements. However, it is essential to approach parameter changes with caution and thoroughly test and validate any modifications to ensure safe and accurate machine tool operation.
In Fanuc CNC systems, Parameter 1860 (APOS) stores the absolute position of each axis
within the machine coordinate system as determined by the absolute pulse coder. en.industryarena.com Parameter Overview Parameter Number : Absolute position (Machine Coordinate) : 2-word axis parameter (Long Integer)
: Detection unit (typically microns or 0.0001 inches, depending on the system's increment settings) en.industryarena.com How It Works When a machine is equipped with Absolute Pulse Coders (APC)
, the CNC does not need to perform a reference return (homing) every time it is powered on. Instead, it reads the current position from the encoder and updates Parameter 1860. Origin Retention
: The value in 1860 is maintained by a battery backup in the pulse coder or servo amplifier. If battery power is lost, the value in 1860 becomes invalid, necessitating a new home position setup. Relation to Parameter 1815 : 1860 works in tandem with Parameter 1815
(APC and APZ bits). Parameter 1815.5 (APC) tells the system an absolute encoder is in use, while 1815.4 (APZ) confirms the zero point has been established. When 1815.4 is set to 1, the value currently in 1860 is recognized as the valid machine position. Coordinate Calculation
: The CNC uses the value in 1860 as the base for all other coordinate systems (Work Offsets G54-G59). If 1860 is incorrect, all machining positions will be shifted. en.industryarena.com Maintenance & Troubleshooting Series 16i/18i/21i/20i-A Maintenance Manual, GFZ-63005EN/02
Every modern FANUC spindle motor comes with a built-in encoder (often a pulse coder with 1024, 2048, or 4096 pulses per revolution). This encoder generates a one-per-revolution (Z) pulse that marks a reference position. However, due to mechanical tolerances in coupling the encoder to the spindle shaft, the Z-pulse rarely aligns exactly with the physical keyway or tool-change orientation required by the machine.
Parameter 1860 controls the Feed per Revolution (FPR) Override limit.
When your G-code program commands a feed rate based on spindle revolutions (e.g., G99 G01 Z-50.0 F0.2), the operator can adjust this feed rate using the Override knob on the control panel (usually 0%, 10%, ..., 150%, 200%).
Parameter 1860 sets the maximum percentage of override the operator can select. Any override selection higher than this parameter’s value will be ignored or clamped to this maximum.