What causes KUKA Robot alarm KRC0991?

Attempting to assign a non-signal data type to a signal variable. Passing an incorrect parameter type to a function that expects a signal object. Using a signal name without proper SIGNAL keyword declaration. Mismatched signal type in structure or array initialization. Incorrect signal reference syntax or missing signal object instantiation.

How do I fix KUKA Robot alarm KRC0991?

1. Review the line of code referenced in the error message and verify the variable or parameter is declared as SIGNAL type 2. Check that all signal assignments use compatible signal data types (e.g., BOOL signals, INT signals) 3. Verify function signatures match the signal types being passed as arguments 4. Ensure SIGNAL keyword is properly used in variable declarations for signal objects 5. Examine related include files or module definitions to confirm signal type consistency across the program 6. Recompile the program after corrections and verify the syntax against KUKA KRL documentation for signal handling

KUKA Robot codes

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KUKA Robot Controller

System · Basic

Alarm KRC0991

KUKA Robot KRC0991 - TYPE EXPNAME OF A SIGNAL EXPECTED 2328

This alarm indicates a type mismatch error where a signal object was expected but a different data type was provided in the KRL program. The compiler encountered an incompatible type assignment or function parameter when processing signal declarations or signal-related operations at error code 2328.

KUKA RobotSystemBasic

KRC0991

KUKA Robot KRC0991 - TYPE EXPNAME OF A SIGNAL EXPECTED 2328

TYPE EXPNAME OF A SIGNAL EXPECTED 2328

Common Causes

Attempting to assign a non-signal data type to a signal variable
Passing an incorrect parameter type to a function that expects a signal object
Using a signal name without proper SIGNAL keyword declaration
Mismatched signal type in structure or array initialization
Incorrect signal reference syntax or missing signal object instantiation

Troubleshooting Steps

1Review the line of code referenced in the error message and verify the variable or parameter is declared as SIGNAL type
2Check that all signal assignments use compatible signal data types (e.g., BOOL signals, INT signals)
3Verify function signatures match the signal types being passed as arguments
4Ensure SIGNAL keyword is properly used in variable declarations for signal objects
5Examine related include files or module definitions to confirm signal type consistency across the program
6Recompile the program after corrections and verify the syntax against KUKA KRL documentation for signal handling

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