What causes KUKA Robot alarm KRC0900?

Comparing or operating on INT, REAL, or other non-boolean variables in a boolean context without proper type casting. Using assignment or comparison operators with mismatched data types where both operands must be BOOL. Attempting logical operations (AND, OR, NOT) on variables declared as incompatible data types. Missing or incorrect type conversion function calls when working with boolean expressions. Incorrect variable declaration or initialization in the KRL program object.

How do I fix KUKA Robot alarm KRC0900?

1. Review the KRL source code at the line number indicated in the error message to identify the problematic boolean expression 2. Verify that all variables used in boolean operations are explicitly declared with BOOL data type 3. Check for implicit type conversions and add explicit casting functions (e.g., BOOL(), INT_TO_BOOL) where necessary 4. Ensure comparison operators are only used between compatible data types and that the result is assigned to BOOL variables 5. Recompile the KRL program after correcting the data type mismatches 6. If the issue persists, consult the KUKA KRL reference guide for proper boolean syntax and consider creating a test program to validate the corrected logic

KUKA Robot codes

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KUKA Robot Controller

System · Basic

Alarm KRC0900

KUKA Robot KRC0900 - BOTH OPERANDS NOT EQUAL TO BOOL 2236

This alarm occurs during KRL program compilation or execution when a comparison or logical operation attempts to use non-boolean operands where boolean values are required. The system detected that at least one operand in a boolean expression is not of the BOOL data type, violating type safety rules.

KUKA RobotSystemBasic

KRC0900

KUKA Robot KRC0900 - BOTH OPERANDS NOT EQUAL TO BOOL 2236

BOTH OPERANDS NOT EQUAL TO BOOL 2236

Common Causes

Comparing or operating on INT, REAL, or other non-boolean variables in a boolean context without proper type casting
Using assignment or comparison operators with mismatched data types where both operands must be BOOL
Attempting logical operations (AND, OR, NOT) on variables declared as incompatible data types
Missing or incorrect type conversion function calls when working with boolean expressions
Incorrect variable declaration or initialization in the KRL program object

Troubleshooting Steps

1Review the KRL source code at the line number indicated in the error message to identify the problematic boolean expression
2Verify that all variables used in boolean operations are explicitly declared with BOOL data type
3Check for implicit type conversions and add explicit casting functions (e.g., BOOL(), INT_TO_BOOL) where necessary
4Ensure comparison operators are only used between compatible data types and that the result is assigned to BOOL variables
5Recompile the KRL program after correcting the data type mismatches
6If the issue persists, consult the KUKA KRL reference guide for proper boolean syntax and consider creating a test program to validate the corrected logic

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