SV0415 Motion Range Exceeded (Soft Shift) fault in Fanuc drive

SV0415 Motion Range Exceeded (Soft Shift) fault in Fanuc drive

Description

SV0415 is a sophisticated soft-limit alarm. Unlike SV0403 (which triggers when you hit a static wall), SV0415 triggers based on a calculation of "Excess Shift." It determines that the commanded move combined with the current error and velocity would push the axis beyond the safe movable range or "stroke limit check" during high-speed operation. It essentially predicts a crash into the soft limit before it physically happens.

Cause

• Erratic Speed: A sudden spike in velocity command causing the "stopping distance" calculation to exceed the remaining travel distance.
• Parameter Setting: The "Excess Shift" threshold parameter (1829 or similar) is set too tight for the rapid rate of the machine.
• Noise: Noise on the encoder signal making it look like the axis teleported toward the limit.

Solution

1. Check Parameters: Review parameter 1828 and 1829. Compare them with the factory backup sheet.
2. Slow Down: If this happens during a specific rapid move near the end of travel, verify the G-code isn't commanding a move right to the edge of the limit at 100% rapid.
3. Reset Limits: Perform a P+CAN startup to temporarily disable the check and move the axis to the center.