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FANUC Controller
Program/G-code · Intermediate · 5-30 minutes
Fanuc 179 - Stroke limit check not performed
Alarm 179 occurs when the CNC control cannot perform stroke limit checking due to missing or invalid machine position data, typically during program execution or mode transitions. This is most commonly caused by attempting to execute motion commands before the machine has established a valid coordinate system through homing/reference point return, or when stroke limit parameters are incorrectly configured.
179
Fanuc 179 - Stroke limit check not performed
STROKE LIMIT CHECK NOT PERFORMED
Fanuc PS program alarm 179: STROKE LIMIT CHECK NOT PERFORMED. This alarm is triggered by an illegal or incorrectly formatted command in the part program, or a programming condition that the Fanuc control cannot execute.
Root Cause Summary
Alarm 179 occurs when the CNC control cannot perform stroke limit checking due to missing or invalid machine position data, typically during program execution or mode transitions. This is most commonly caused by attempting to execute motion commands before the machine has established a valid coordinate system through homing/reference point return, or when stroke limit parameters are incorrectly configured.
Safety
- Verify corrected program or parameters before resuming machining
Causes and Fixes
- 1
Check the machine reference point status on the position display screen. Look for asterisks (*) or warning indicators next to axis positions indicating unreferenced axes.
- 2
Perform manual reference point return for all axes. Select REF (reference) mode on the mode selector and execute zero return for each axis using the axis direction buttons.
Ensure the machine work area is clear and no obstructions are present before performing reference return.
- 3
Verify that all axes show reference point established (asterisks disappear or REF indicator lights up) on the position display.
- 4
Reset the alarm using the RESET button and attempt to run the program again.
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