In the world of FANUC CNC systems, Parameter 1860 is a critical, though often misunderstood, data field that serves as the digital link between the machine's physical location and its internal coordinate system. For technicians and engineers, mastering this parameter is essential for maintaining the high-precision "memory" of a machine tool. The Role of Absolute Position Detectors
To understand Parameter 1860, one must first look at how modern CNC machines track movement. Most contemporary systems use Absolute Pulse Coders (APC)
. Unlike incremental encoders that "forget" where they are when the power is cut, absolute encoders maintain their position even when the machine is off, provided they have battery backup. Parameter 1860 is where the system stores the current position data
received from these absolute pulse coders. It functions as a real-time ledger, recording the exact number of pulses or counts the encoder has moved from its established reference point. The Technical Mechanism
While many parameters are meant to be manually toggled by an operator (like Parameter 1815
, which establishes the zero point), Parameter 1860 is typically or updated automatically by the system. Modular Arithmetic
: The value in 1860 often uses modular arithmetic, meaning the count "wraps around" once it reaches a certain limit based on the encoder's resolution. Relationship to Zeroing
: When a technician performs a zero-return or resets the absolute position (often by toggling the APZ bit in Parameter 1815), the system recalibrates the relationship between the machine's physical "home" and the count currently residing in Parameter 1860. Why Parameter 1860 Matters
For most daily operations, a machinist will never need to look at 1860. However, it becomes vital in two specific scenarios: Recovery from APC Alarms
: If the encoder batteries die (Alarms 300-349), the machine loses its reference. While 1815 is used to tell the machine "this is zero," Parameter 1860 is where the raw data behind that zero point is tracked. Diagnostics
: If a machine is losing its position or "drifting," technicians check 1860 to see if the encoder is reporting counts correctly. If the value in 1860 changes when the axis is physically stationary—perhaps due to a failing brake or electrical noise—it signals a hardware failure. Conclusion Parameter 1860 is the "silent partner" of the more famous Parameter 1815
. While 1815 sets the rules for homing, 1860 provides the raw data that makes absolute positioning possible. Understanding its role ensures that when a machine loses its way, a technician has the diagnostic insight to bring it back to a precise home. reset the zero point using parameters 1815 and 1860 after a battery failure? FANUC? M6 toolchange position. | Practical Machinist 21 May 2014 —
In the world of FANUC CNC systems, Parameter 1860 is a critical setting used primarily for machines equipped with absolute position detectors. It stores the current position of each axis relative to the machine zero point, ensuring the CNC "remembers" where it is even after a power cycle. What is FANUC Parameter 1860?
Parameter 1860 is a 2-word (32-bit) axis parameter. Its primary function is to maintain the absolute position data provided by the encoder. When a machine uses an absolute encoder, it doesn't need to be "homed" or "zero-returned" every morning; instead, it reads the value stored in this parameter to determine its exact location.
Data Type: 2-word (often works in conjunction with high-order bits in nearby parameters).
Key Function: Synchronizing the mechanical position of the machine with the internal coordinate system. When Does Parameter 1860 Become Important?
You will typically need to interact with this parameter during:
Battery Replacement: If the encoder batteries die, the absolute position is lost, and Parameter 1860 may need to be reset.
Motor/Encoder Replacement: Installing a new servo motor requires re-establishing the relationship between the physical axis and the CNC's internal logic.
Mechanical Crashes: A severe impact can jump the encoder or move the physical axis, making the stored value in 1860 inaccurate. Related Alarms
If there is an issue with the absolute position data, you may encounter specific APC (Absolute Pulse Coder) alarms:
Alarm 300: Request for zero return (the system has lost its position).
Alarm 306-308: Battery-related errors indicating the absolute position data is at risk. How to Set or Reset the Absolute Position fanuc parameter 1860
Resetting the absolute position is a precise process that involves both Parameter 1860 and Parameter 1815. Master the Fanuc Zero Return Procedure in 5 Steps
Fanuc Parameter 1860 stores the current position data of the absolute pulse coder (APC) for each axis.
This parameter is a critical internal value that represents the absolute position of the axis relative to the reference point (home). When a machine is equipped with absolute encoders, it "remembers" its position even after being powered off. Parameter 1860 acts as the digital record of that specific physical location on the encoder's scale. Role in Absolute Homing
Data Persistence: Unlike incremental encoders that require a fresh "Zero Return" ( G28cap G 28
) at every startup, absolute encoders use Parameter 1860 to retain the machine's coordinate values.
Automatic Update: This is typically a "read-only" parameter for general operation; the CNC system updates it automatically as the axis moves.
Relationship to 1815: It works in conjunction with Parameter 1815 (APC and APZ bits), which tells the system whether an absolute encoder is present and if the zero-point has been established. When 1860 Matters
You will likely interact with or notice this parameter during specific maintenance scenarios:
Encoder Battery Failure: If the backup battery dies, the absolute position is lost. Parameter 1860 may reset or become invalid, requiring a manual re-homing procedure to re-establish the relationship between the physical machine position and the digital value.
Motor or Encoder Replacement: Replacing the hardware requires a "zeroing" procedure that writes a new reference value into Parameter 1860.
Position Alarms: Alarms such as "APC Alarm: Need ZRN" often indicate a mismatch or loss of the data stored in this parameter. How to Modify (If Required)
Directly editing 1860 is rare and usually unnecessary because the "Zero Return" procedure updates it automatically. However, if you must change parameters:
Enable Parameter Write: Navigate to the SETTING screen and set PARAMETER WRITE (PWE) to 1.
System Alarm: The machine will typically go into an Emergency Stop or P/S 100 state while PWE is enabled.
Locate Parameter: Press the SYSTEM key, then the PARAM softkey, and type 1860 followed by [NO. SRH]. How to Enable Parameter Write Enable (PWE) on a Fanuc CNC
Fanuc Parameter 1860 is a critical axis-specific setting used to define the absolute position of a machine tool's moving parts. It essentially serves as the "memory" for where an axis is located after the machine has been powered off. 📍 Purpose and Function
This parameter stores the current position of an axis in relation to the machine’s reference point (home). It is primarily used with absolute encoders (detectors).
Unlike incremental encoders, which require a "homing" sequence every time you turn on the machine, absolute encoders use this parameter to remember their last known position.
The value is expressed in detection units (the smallest increment the CNC can track). ⚙️ When to Modify Parameter 1860
You typically do not manually "type in" a value for this parameter. Instead, the CNC system updates it automatically during specific procedures:
Battery Replacement: If the backup battery for the absolute pulsecoder dies while the power is off, the absolute position is lost. You must re-establish the home position.
Mechanical Repairs: If you disconnect a motor, replace a ballscrew, or move the axis manually while the power is off, the value in 1860 will no longer match the physical reality. In the world of FANUC CNC systems, Parameter
Grid Shift Adjustments: When fine-tuning the exact "zero" point of the machine for accuracy. ⚠️ Common Alarms Related to 1860
If the value in Parameter 1860 is corrupted or doesn't match the expected feedback, the CNC will trigger an alarm to prevent crashes:
300 APC ALARM: NEED REF RETURN: The system knows the position is invalid and requires you to perform a manual reference return.
306 APC ALARM: BATTERY VOLTAGE 0: The battery died; Parameter 1860 data is likely lost. 🛠️ How to Reset the Position
To refresh the data in Parameter 1860, follow the Reference Position Setting (often referred to as "homing the absolute axis"): Set Parameter 1815 bit 4 (APZ) to 0 for the specific axis. Restart the machine (this clears the old position). Manually move the axis to the desired "Home" position. Set Parameter 1815 bit 4 (APZ) back to 1.
Cycle the power; the CNC will now write the new position into Parameter 1860.
💡 Pro Tip: Always back up your parameters before making changes. You can follow guides from Fanuc Support or retailers like CNC Electronics for specific model variations. If you're dealing with a specific alarm right now, tell me: The exact alarm number on the screen. Which axis is affected (X, Y, Z, etc.). Your CNC model (e.g., Series 0i-MD, 18i-TB).
In FANUC CNC systems, Parameter 1860 a critical coordinate-related parameter used to store the current position of an axis when using an absolute pulse coder (APC)
. It essentially serves as the CNC's internal memory for where the machine tool is located in space even after the power is turned off. Core Function and Purpose Position Retention:
Unlike incremental encoders that require a homing sequence (zero return) every time the machine is powered up, an absolute encoder remembers its position. Parameter 1860 holds this numerical value for each controlled axis. System Correspondence:
It maintains the mathematical relationship between the mechanical position of the machine and the electronic pulses sent by the encoder. Relation to Parameter 1815 Parameter 1860 works in tandem with Parameter 1815 , which manages the absolute encoder's status: en.industryarena.com APC (1815 bit 5): Indicates if an absolute position coder is being used. APZ (1815 bit 4):
This bit tells the system if the reference position (zero point) has been established. When you set the home position manually, the system updates Parameter 1860 with the current coordinate and then automatically flips the APZ bit to "1" to confirm the zero point is set. en.industryarena.com When to Modify or Check Parameter 1860 Losing Home Position:
If the backup battery for the absolute encoder fails, the system loses the data in Parameter 1860, resulting in a "300 APC Alarm: Need ZRN" (Zero Return Needed). Motor or Encoder Replacement:
When a motor or encoder is swapped, the physical link to the previous "zero" is broken. You must reset the reference position, which clears and updates the value in Parameter 1860. Mechanical Realignment:
If the machine's physical home position needs to be shifted (e.g., after a crash or maintenance), technicians may manually adjust the value in 1860 or perform a new zero-set sequence to overwrite it. en.industryarena.com Safety Warning
Modifying coordinate parameters like 1860 can cause the machine to "think" it is in a different location than it physically is. Incorrect settings can lead to machine crashes overshooting stroke limits . Always back up your parameters before making changes. Fryer Machine Systems Are you currently troubleshooting a "300 APC Alarm" or looking for the specific manual steps to reset your home position? Fanuc > Resetting Reference Position For Absolute Encoder
1. Navigate to the parameter lock. Change it from a zero to a one. 3. Press the SYSTEM hard key and navigate to parameter 1815 en.industryarena.com
Understanding FANUC Parameter 1860: A Comprehensive Guide
FANUC is a well-known Japanese company that specializes in the development and manufacture of CNC (Computer Numerical Control) systems, robots, and other industrial automation products. FANUC's CNC systems are widely used in various industries, including machining, aerospace, and automotive, to name a few. One of the key aspects of FANUC's CNC systems is their parameterization, which allows users to customize and optimize their machines for specific applications. In this article, we will focus on FANUC parameter 1860, its significance, and how to use it effectively.
What is FANUC Parameter 1860?
FANUC parameter 1860 is a specific setting within the FANUC CNC system that controls the "External Machine Stop" function. This parameter allows users to configure the CNC system to stop the machine under specific conditions, such as when an external signal is received or when a certain program event occurs. The External Machine Stop function is essential in many applications, as it enables the operator to quickly and safely stop the machine in case of an emergency or when performing routine maintenance.
Why is FANUC Parameter 1860 Important?
The External Machine Stop function, controlled by parameter 1860, plays a crucial role in ensuring the safety of operators and preventing damage to the machine. Here are some reasons why FANUC parameter 1860 is important:
How to Set FANUC Parameter 1860
Setting FANUC parameter 1860 requires a basic understanding of the FANUC CNC system and its parameterization. Here are the steps to set parameter 1860:
Common Applications of FANUC Parameter 1860
FANUC parameter 1860 is commonly used in various applications, including:
Troubleshooting FANUC Parameter 1860
If issues arise with FANUC parameter 1860, here are some troubleshooting steps:
Conclusion
FANUC parameter 1860 is a critical setting in the FANUC CNC system that controls the External Machine Stop function. By understanding the significance of this parameter and how to set it correctly, users can ensure the safe and efficient operation of their machines. Whether you're a seasoned CNC programmer or a newcomer to the world of CNC machining, this article has provided you with a comprehensive guide to FANUC parameter 1860. By applying the knowledge gained from this article, you can optimize your machine's performance, improve safety, and reduce downtime.
In the FANUC control system, Parameter 1860 (often referred to as a critical bit-type parameter used to indicate whether the absolute position of an axis has been established Core Function: Absolute Position Zero (APZ) Parameter 1860 is an Axis Parameter
. Each axis (X, Y, Z, etc.) has its own bit 4 (the 5th bit from the right) designated as APZ.
The absolute position of the axis has not been established. This usually occurs after a battery failure in the absolute encoder or after moving the motor while the power is off. In this state, the machine will often throw a 300 APC ALARM: NEED ZRN (Zero Return).
The absolute position has been successfully established and the machine "knows" where it is relative to the machine zero. Relationship with Parameter 1815 Parameter 1860 is frequently used in conjunction with Parameter 1815 , which manages the absolute pulse coder settings: 1815 bit 5 (APC): Specifies whether an absolute pulse coder is being used. 1815 bit 4 (APZ):
Like 1860, this bit also indicates if the reference position is set. On many modern FANUC controls (like the 0i or 31i series), 1815 is the primary parameter for setting zero, while 1860 may serve as a status bit or be specific to certain older software versions. When to Modify Parameter 1860 You typically only interact with this parameter during a Reference Position Return (Homing) procedure after a battery replacement or encoder swap: Enable Parameter Write: screen, change PARAMETER WRITE Navigate to Parameter: Go to the System parameters and find 1860. Perform Homing: Manually jog the axis to the physical home position. Change the APZ bit for that axis from 0 to 1.
Cycle the machine power to clear the alarm and finalize the position. Machine Metrics Safety Warning
Modifying positioning parameters can cause machine crashes if the physical location of the axis does not match the value set in the control. Always verify that the soft limits ( Parameter 1320/1321
) and the physical home position are correct before running any programs in automatic mode. irp-cdn.multiscreensite.com Do you need the specific step-by-step procedure
for resetting the home position on a particular FANUC model? How to Enable Parameter Write Enable (PWE) on a Fanuc CNC
Many machinists confuse these two. Here is a simple memory aid:
Never use 1860 to compensate for a misaligned mechanical zero. That is what 1850 is for. Incorrectly raising 1860 to force alignment will only lead to erratic behavior and possible drive failure.
Parameter 1860 (often displayed as PRM 1860) defines the decelerated feedrate that an axis uses after it detects the reference return deceleration dog (limit switch) during a manual or automatic reference position return (G28).
Cause: 1860 may be correct, but the zero-point offset (Parameter 1850) is misaligned. However, a badly tuned 1860 can also cause “soft lock” – the spindle is electrically oriented but not rigid enough to resist tool change insertion forces. Safety : The External Machine Stop function allows
Solution: Increase 1860 by 200-300 units incrementally while listening for mechanical compliance during a manual tool change.