What causes KUKA Robot alarm KRC0498?

Using $OUT_C command directly in an INTERRUPT routine definition. Calling a subprogram containing $OUT_C from within an interrupt handler. Attempting to set digital outputs in an interrupt-triggered program block. Using output assignment statements (e.g., $OUT[n]=TRUE) within INTERRUPT code sections. Legacy code migration where output commands were not refactored out of interrupt handlers.

How do I fix KUKA Robot alarm KRC0498?

1. Identify the INTERRUPT routine in your KRL program that contains the $OUT_C or output command causing the alarm 2. Remove all $OUT_C, $OUT[], and digital/analog output assignments from the interrupt program block 3. Refactor output operations into a separate non-interrupt subprogram or main program section 4. Use a flag variable set in the interrupt routine to signal the main program to execute the output command 5. Verify the interrupt routine only contains permissible instructions (arithmetic, logic, flag setting, and synchronization commands) 6. Recompile the program and test the interrupt logic to ensure outputs occur at the correct time through the main program flow

KUKA Robot codes

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KUKA Robot Controller

Program/G-code · Basic

Alarm KRC0498

KUKA Robot KRC0498 - $OUT_C[N] IS NOT PERMISSIBLE IN INTERRUPT PROGRAMS

This alarm indicates that an output command ($OUT_C) has been used within an interrupt program (INTERRUPT routine), which is not permitted in the KUKA KRC controller. Output commands that control digital or analog outputs cannot be executed in interrupt handlers because they may cause timing conflicts and unpredictable behavior. Interrupt programs must be restricted to time-critical logic and cannot perform I/O operations that could interfere with main program execution.

KUKA RobotProgram/G-codeBasic

KRC0498

KUKA Robot KRC0498 - $OUT_C[N] IS NOT PERMISSIBLE IN INTERRUPT PROGRAMS

$OUT_C[N] IS NOT PERMISSIBLE IN INTERRUPT PROGRAMS

Common Causes

Using $OUT_C command directly in an INTERRUPT routine definition
Calling a subprogram containing $OUT_C from within an interrupt handler
Attempting to set digital outputs in an interrupt-triggered program block
Using output assignment statements (e.g., $OUT[n]=TRUE) within INTERRUPT code sections
Legacy code migration where output commands were not refactored out of interrupt handlers

Troubleshooting Steps

1Identify the INTERRUPT routine in your KRL program that contains the $OUT_C or output command causing the alarm
2Remove all $OUT_C, $OUT[], and digital/analog output assignments from the interrupt program block
3Refactor output operations into a separate non-interrupt subprogram or main program section
4Use a flag variable set in the interrupt routine to signal the main program to execute the output command
5Verify the interrupt routine only contains permissible instructions (arithmetic, logic, flag setting, and synchronization commands)
6Recompile the program and test the interrupt logic to ensure outputs occur at the correct time through the main program flow

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