What causes KUKA Robot alarm KRC0906?

Using a string or array variable where a primitive type (INT, REAL, BOOL, CHAR) is expected. Attempting to perform arithmetic or logical operations on incompatible data types without proper type casting. Passing a variable of incorrect type as an argument to a function or procedure. Declaring or assigning a value to a variable that conflicts with its declared data type. Using an unsupported or custom data structure where only standard KUKA data types are allowed.

How do I fix KUKA Robot alarm KRC0906?

1. Review the KRL program at the line number indicated in the alarm message and identify the problematic operand or variable 2. Verify the declared data type of the variable in question by checking its declaration statement in the program 3. Confirm that the operand type matches the expected input type for the operation or function being called 4. If necessary, add explicit type casting or conversion functions (e.g., INT(), REAL(), BOOL()) to convert the operand to the required type 5. Consult the KUKA KRL reference manual for the specific function or instruction to verify correct operand type requirements 6. Recompile or reload the KRL program after making corrections and verify the alarm no longer occurs

KUKA Robot codes

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KUKA Robot Controller

System · Basic

Alarm KRC0906

KUKA Robot KRC0906 - OPERANDS NOT EQUAL TO INT, REAL, BOOL, CHAR, ENUM 2243

This alarm indicates a type mismatch error in KRL code where an operand or variable does not match the required data types (INT, REAL, BOOL, CHAR, or ENUM). The compiler or interpreter cannot process the operation because the operand type is incompatible with the expected type for the instruction or function call.

KUKA RobotSystemBasic

KRC0906

KUKA Robot KRC0906 - OPERANDS NOT EQUAL TO INT, REAL, BOOL, CHAR, ENUM 2243

OPERANDS NOT EQUAL TO INT, REAL, BOOL, CHAR, ENUM 2243

Common Causes

Using a string or array variable where a primitive type (INT, REAL, BOOL, CHAR) is expected
Attempting to perform arithmetic or logical operations on incompatible data types without proper type casting
Passing a variable of incorrect type as an argument to a function or procedure
Declaring or assigning a value to a variable that conflicts with its declared data type
Using an unsupported or custom data structure where only standard KUKA data types are allowed

Troubleshooting Steps

1Review the KRL program at the line number indicated in the alarm message and identify the problematic operand or variable
2Verify the declared data type of the variable in question by checking its declaration statement in the program
3Confirm that the operand type matches the expected input type for the operation or function being called
4If necessary, add explicit type casting or conversion functions (e.g., INT(), REAL(), BOOL()) to convert the operand to the required type
5Consult the KUKA KRL reference manual for the specific function or instruction to verify correct operand type requirements
6Recompile or reload the KRL program after making corrections and verify the alarm no longer occurs

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