What causes FANUC alarm 1098?

Machine system or function indicated by the alarm name has detected a fault. Control parameter or configuration error related to the alarm condition. Hardware component fault on the CNC or machine. Part program error or illegal operation for the indicated function. Machine interlock or safety condition not satisfied.

How do I fix FANUC alarm 1098?

1. Note the alarm number and check the Fanuc alarm screen for any sub-code or additional details. 2. Identify the specific machine system or function from the alarm name. 3. Power cycle the machine to clear transient faults. 4. Consult the Fanuc parameter or operator manual for alarm 1098 specific remedy. 5. Contact Fanuc service if the alarm persists after basic troubleshooting.

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FANUC Controller

Program/G-code · Intermediate · 20-45 minutes

Alarm 1098

Fanuc Alarm 1098 - NO VARIABLE NAME

Fanuc Alarm 1098 occurs when a macro program references a common variable name (user-defined variable) that has not been registered in the system variable name table. This typically happens when using symbolic variable names in custom macro B programs without proper declaration in parameter 27700 series or when the variable name definition has been cleared or corrupted.

FANUCProgram/G-codeIntermediate20-45 minutes

1098

Fanuc Alarm 1098 - NO VARIABLE NAME

SYSTEM ALARM 1098

Root Cause Summary

Fanuc Alarm 1098 occurs when a macro program references a common variable name (user-defined variable) that has not been registered in the system variable name table. This typically happens when using symbolic variable names in custom macro B programs without proper declaration in parameter 27700 series or when the variable name definition has been cleared or corrupted.

Causes and Fixes

1
Navigate to SYSTEM > PARAM and search for parameter series 27700-27899. Check if the variable name referenced in the alarm is registered. Each parameter can hold one variable name definition.
2
Review the macro program line causing the alarm and identify the exact variable name being called (e.g., #<_TOOLOFFSET> or similar symbolic name).
3
Register the missing variable name in an available parameter slot between 27700-27899. Enter the exact variable name string including angle brackets and underscores as used in the program.
Parameter write enable (PWE) must be set to 1 using the key switch or parameter 3202#0=1 to modify these parameters.
4
Power cycle the CNC control (full power off/on) to ensure variable name table is properly initialized with new registrations. Reset alarm and re-run program.

DIY Feasiblehigh confidence

Call a technician if:

·Parameter corruption requiring system restore
·Hardware memory issues
·Control software compatibility problems

Prevention

Always initialize macro variables before use
Document variable usage and ranges
Use consistent variable naming conventions
Regularly backup macro programs and variable tables

Common Mistakes

Forgetting to pass local variables in G65 calls
Using undefined variable numbers
Mixing up local and global variable ranges
Not checking control model compatibility for system variables

Related Alarms

1097 1099 1100 1101

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