Fanuc Parameter 1829 ((link)) Direct

Observe the values assigned to each axis (e.g., X, Y, Z, and the spindle). Step 4: Analyze and Adjust the Value

As one experienced technician explains: "The CNC uses the position error specified in par 1828 when it is commanded to move. At the end of the block, the axis is no longer commanded to move, so it uses the error zone specified in par 1829. If it overshoots that zone, alarm 410 occurs".

Excessive friction from worn ways or bearings that the motor can't overcome to maintain position Servo Tuning Issues:

To understand Parameter 1829, you must first understand the position loop. A CNC servo system operates on nested feedback loops: Controls torque. Velocity Loop: Controls axis speed. fanuc parameter 1829

Lack of oil on box ways or linear guides increases friction, making it harder for the servo motor to maintain speed.

Inspect the motor feedback cables for damage. An intermittent encoder signal can cause the controller to see a shifting position. 5. Check Acceleration Time Constants

It monitors axis stability when not moving. If an axis drifts or is pushed out of position while stopped, this parameter catches the error. Comparison: It works alongside Parameter 1828 , which sets the limit for deviation while the axis is Common Causes for Alarm 410: Mechanical Issues: Observe the values assigned to each axis (e

Ensure the automatic lubrication system is functioning and that the ways aren't dry Monitor Position Deviation: Use the CNC's Diagnosis Screen

Note: The value is typically calculated based on the maximum feedrate, position loop gain (Parameter 1825), and detection units. The standard formula provided by FANUC guidelines is:

sets the position deviation limit when the axis is moving . Because an axis requires more tolerance to accelerate, decelerate, and fight cutting forces while moving, the value in 1829 is almost always significantly larger than the value in 1828. The Consequence: Alarm SV0411 (Excess Error) If it overshoots that zone, alarm 410 occurs"

When operating a FANUC CNC machine, encountering axis jerk, poor surface finishes, or sudden servo alarms can bring production to a grinding halt. Often, the root cause lies within the servo tuning parameters. One of the most critical, yet frequently misunderstood, settings in a FANUC control system is .

When a CNC machine is in motion, there is always a tiny, calculated delay between the position command sent by the CNC software and the actual physical position of the servo motor. This lag is called or following error .