What causes FANUC alarm 318?

Incorrect delta-d value specified in the G74 or G75 drilling cycle. Mismatch between the escape direction and the delta-d value in the drilling cycle. Syntax error in the G-code program related to the drilling cycle parameters.

How do I fix FANUC alarm 318?

1. Carefully review the G-code program and locate the G74 or G75 drilling cycle block where the alarm occurred. 2. Verify that the delta-d value specified in the drilling cycle is a positive number, as required by the cycle. 3. Check that the escape direction set in the cycle matches the sign of the delta-d value. 4. If the delta-d value is correct, inspect the rest of the drilling cycle parameters to ensure there are no other syntax errors. 5. Correct the delta-d value or any other issues in the drilling cycle block and rerun the program. 6. If the alarm persists, check for any other G-code errors or issues that may be causing the problem.

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FANUC Controller

Program/G-code · Intermediate · 15-30 minutes

Alarm 318

Fanuc Alarm 318 - ILLEGAL RELIEF AMOUNT IN DRILLING CYCLE

Alarm 318 occurs when using G74 (peck drilling/face grooving) or G75 (OD/ID grooving) multiple repetitive cycles with an escape/relief move direction specified, but the delta-d (incremental relief amount) parameter is programmed as a negative value. The control expects a positive delta-d value to determine the retract distance after each cut when relief is enabled.

FANUCProgram/G-codeIntermediate15-30 minutes

318

Fanuc Alarm 318 - ILLEGAL RELIEF AMOUNT IN DRILLING CYCLE

MISSING ESCAPE DIRECTION IN G74/G75

Root Cause Summary

Alarm 318 occurs when using G74 (peck drilling/face grooving) or G75 (OD/ID grooving) multiple repetitive cycles with an escape/relief move direction specified, but the delta-d (incremental relief amount) parameter is programmed as a negative value. The control expects a positive delta-d value to determine the retract distance after each cut when relief is enabled.

Causes and Fixes

1
Review the active G74 or G75 program block. Check the syntax: G74/G75 R(e) where e is the escape/relief amount, followed by G74/G75 X__ Z__ P__ Q__ R__ F__ where Q is delta-d (incremental cut depth).
2
Verify that the Q value (delta-d) is programmed as a positive radius/diameter value without a negative sign. Example: G75 R0.5; followed by G75 X30. Z-20. P5000 Q500 F0.15; - the Q500 must be positive.
3
If relief is required, ensure the first G74/G75 block specifies R(e) with appropriate escape amount, then verify delta-d is positive. If no relief is needed, remove the R parameter from the first G74/G75 block entirely.
4
Correct the program by changing delta-d to a positive value or removing the relief specification. Reset alarm with RESET key, return to program start position, and restart cycle.

DIY Feasiblehigh confidence

Call a technician if:

·Parameter P5101 is locked and cannot be modified
·Control software version compatibility issues persist

Prevention

Always use positive delta-d values when escape direction is enabled
Validate G74/G75 syntax against your specific Fanuc control manual
Test new canned cycles in single block mode first

Common Mistakes

Confusing delta-d sign convention with cutting direction
Not checking parameter P5101 setting before programming
Copying G74/G75 programs between different Fanuc control series without verification

Related Alarms

317 319 320

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