What causes KUKA Robot alarm KRC0490?

Tool frame ($TOOL) was never initialized in the program startup or declaration section. Tool data file is missing or not loaded in the robot's tool database. Program references a tool number that does not exist in the system configuration. Incorrect syntax used when assigning tool frame values (wrong variable name or format). Tool frame was deleted or cleared during program execution without reassignment.

How do I fix KUKA Robot alarm KRC0490?

1. Verify that a $TOOL assignment statement exists in the program before any motion commands that require tool data 2. Check the tool configuration file (typically in /KRC/Roboter/Tool or equivalent directory) and confirm the tool is properly defined 3. Use the KUKA teach pendant to manually define the tool frame if not already created, or import from an existing tool library 4. Confirm the syntax of the $TOOL assignment matches KRL language standards (e.g., $TOOL = Tool[X,Y,Z,A,B,C] or similar) 5. Review the program initialization section and ensure tool data is loaded before any motion commands are executed 6. Reload the tool database and restart the program execution cycle after making corrections

KUKA Robot codes

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KUKA Robot Controller

Program/G-code · Advanced

Alarm KRC0490

KUKA Robot KRC0490 - <X,Y,Z,A,B,C> TOOL not programmed

This alarm indicates that the tool coordinate frame ($TOOL) has not been defined or assigned a value in the active robot program before execution. The KUKA KRC controller requires a valid tool frame definition to properly calculate TCP (Tool Center Point) offsets and orientation for any subsequent motion commands involving tool-dependent operations.

KUKA RobotProgram/G-codeAdvanced

KRC0490

KUKA Robot KRC0490 - <X,Y,Z,A,B,C> TOOL not programmed

<X,Y,Z,A,B,C> TOOL not programmed

Common Causes

Tool frame ($TOOL) was never initialized in the program startup or declaration section
Tool data file is missing or not loaded in the robot's tool database
Program references a tool number that does not exist in the system configuration
Incorrect syntax used when assigning tool frame values (wrong variable name or format)
Tool frame was deleted or cleared during program execution without reassignment

Troubleshooting Steps

1Verify that a $TOOL assignment statement exists in the program before any motion commands that require tool data
2Check the tool configuration file (typically in /KRC/Roboter/Tool or equivalent directory) and confirm the tool is properly defined
3Use the KUKA teach pendant to manually define the tool frame if not already created, or import from an existing tool library
4Confirm the syntax of the $TOOL assignment matches KRL language standards (e.g., $TOOL = Tool[X,Y,Z,A,B,C] or similar)
5Review the program initialization section and ensure tool data is loaded before any motion commands are executed
6Reload the tool database and restart the program execution cycle after making corrections

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