What causes FANUC alarm OT0510?

Part program commands movement beyond the configured C+ axis software travel limit. Work coordinate offset (G54-G59) or tool length compensation error placing the programmed position outside the travel envelope. Axis homing not completed — software travel limits are not enforced until the axis returns to its reference position. Axis travel limit parameter (parameters 1320/1321 for stored stroke check 1, 1322/1323 for check 2) incorrectly set. Manual jog in JOG or HANDLE mode moved the axis past the software limit.

How do I fix FANUC alarm OT0510?

1. Jog the axis in the opposite direction (away from the limit) to clear the overtravel and allow the alarm to be reset. 2. After clearing the alarm, verify the part program coordinates and active work offsets are within the machine travel envelope. 3. Check tool length compensation values — an incorrect H-code value can place the tool path outside travel limits. 4. Verify the machine has completed its reference return — software stroke limits are inactive until homing is done. 5. Check the stroke limit parameters (1320/1321 series) against the machine's actual mechanical travel range.

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FANUC Controller

Overtravel/Limit · Basic · 10-20 minutes

Alarm OT0510

Fanuc Alarm OT0510 - C-Axis Positive Overtravel

Fanuc alarm OT0510 occurs when the C-axis (rotary spindle or rotary table) has traveled beyond its programmed positive software limit or physical hardware overtravel limit. This is typically caused by incorrect travel limit parameters, mechanical interference, incorrect workpiece coordinate system offsets, or faulty overtravel limit switch hardware on systems with hardware limits enabled.

FANUCOvertravel/LimitBasic10-20 minutes

OT0510

Fanuc Alarm OT0510 - C-Axis Positive Overtravel

Overtravel +C

Root Cause Summary

Fanuc alarm OT0510 occurs when the C-axis (rotary spindle or rotary table) has traveled beyond its programmed positive software limit or physical hardware overtravel limit. This is typically caused by incorrect travel limit parameters, mechanical interference, incorrect workpiece coordinate system offsets, or faulty overtravel limit switch hardware on systems with hardware limits enabled.

Safety

Cable wrap may be stressed

Causes and Fixes

1
Navigate to SYSTEM > PARAM and check parameter 1321 (positive side software limit for C-axis, typically axis number 4 or 6 depending on configuration). Verify this value matches the mechanical positive limit of your C-axis in degrees (typically 0 to 360 or +/-9999 for continuous rotation).
2
Check parameter 1006 bit 1 (OTx) to verify software overtravel check is enabled. If bit 1=1, software limits are active. Check parameter 1420/1421 for C-axis if dual-level limits are configured on 30i/31i/32i systems.
3
Navigate to POSITION screen (POS key) and check the current C-axis MACHINE coordinate position. Compare this to parameter 1321 limit. If the machine coordinate exceeds the limit, perform a manual return using overtravel release: Hold OT RELEASE button + manual jog in negative direction.
Ensure no mechanical obstruction exists before performing overtravel release. Move axis slowly in small increments.
4
Verify work coordinate offsets (G54-G59) via OFFSET/SETTING > WORK ZERO OFFSET screen. Excessive positive offset in C-axis can cause program positions to exceed limits even when workpiece coordinates appear normal. Adjust or reset offsets as needed.

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