What causes KUKA Robot alarm KRC0903?

Attempting to perform arithmetic or logical operations between incompatible data types (e.g., BOOL with INT). Using a STRUCT or ARRAY type in a binary operation that requires primitive data types. Mixing user-defined types or AXIS types with INT/REAL/CHAR/ENUM in expressions. Passing incorrect parameter types to functions expecting INT, REAL, CHAR, or ENUM arguments. Implicit type casting issues where the compiler cannot automatically convert operand types.

How do I fix KUKA Robot alarm KRC0903?

1. Review the KRL source code line referenced in the alarm message to identify the problematic expression or operation 2. Verify that both operands in the operation are declared with compatible types: INT, REAL, CHAR, or ENUM 3. Check function/procedure declarations and ensure passed arguments match the expected parameter types 4. Use explicit type conversion functions (e.g., INT(), REAL()) if type conversion is necessary 5. Validate variable declarations and ensure no STRUCT, ARRAY, or custom types are being used where primitive types are required 6. Recompile the KRL program after corrections and clear any cached code using the KUKA teach pendant

KUKA Robot codes

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KUKA Robot Controller

System · Basic

Alarm KRC0903

KUKA Robot KRC0903 - BOTH OPERANDS NOT EQUAL TO INT, REAL, CHAR, ENUM 2240

This alarm indicates a type mismatch in a KRL program operation where both operands of an expression are not compatible INT, REAL, CHAR, or ENUM data types. The operation cannot proceed because the system cannot perform the requested computation or comparison between the incompatible data types provided.

KUKA RobotSystemBasic

KRC0903

KUKA Robot KRC0903 - BOTH OPERANDS NOT EQUAL TO INT, REAL, CHAR, ENUM 2240

BOTH OPERANDS NOT EQUAL TO INT, REAL, CHAR, ENUM 2240

Common Causes

Attempting to perform arithmetic or logical operations between incompatible data types (e.g., BOOL with INT)
Using a STRUCT or ARRAY type in a binary operation that requires primitive data types
Mixing user-defined types or AXIS types with INT/REAL/CHAR/ENUM in expressions
Passing incorrect parameter types to functions expecting INT, REAL, CHAR, or ENUM arguments
Implicit type casting issues where the compiler cannot automatically convert operand types

Troubleshooting Steps

1Review the KRL source code line referenced in the alarm message to identify the problematic expression or operation
2Verify that both operands in the operation are declared with compatible types: INT, REAL, CHAR, or ENUM
3Check function/procedure declarations and ensure passed arguments match the expected parameter types
4Use explicit type conversion functions (e.g., INT(), REAL()) if type conversion is necessary
5Validate variable declarations and ensure no STRUCT, ARRAY, or custom types are being used where primitive types are required
6Recompile the KRL program after corrections and clear any cached code using the KUKA teach pendant

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