KUKA Robot codes
KUKA RobotSystemAdvanced

KRC0559

KUKA Robot KRC0559 - Combination of variables not allowed <block number>

Combination of variables not allowed <block number>

This alarm indicates that a SYNACT instruction contains an invalid combination of variables where individual movement blocks and approximate positioning blocks are mixed together in logic comparison or value assignment operations. The SYNACT monitoring function requires consistent variable classification and cannot correlate block types that have fundamentally different execution characteristics.

Common Causes

  • SYNACT block combines variables from standard LIN or CIRC blocks with variables from approximate positioning APPR_MOD blocks
  • Logic comparison in SYNACT tries to establish conditional relationships between discrete motion blocks and continuous interpolation blocks
  • Value assignment operation within SYNACT simultaneously references block-specific variables across different block category types
  • Program structure mixes PTP movement variable monitoring with linear interpolation variable monitoring in a single SYNACT instruction
  • Incorrect SYNACT parameterization attempts to synchronize blocks with incompatible execution models or interpolation methods

Troubleshooting Steps

  1. 1Review the SYNACT instruction definition and identify all referenced block numbers and their corresponding motion command types
  2. 2Separate the SYNACT instruction into multiple independent SYNACT blocks, each handling a single consistent block type category
  3. 3Create one SYNACT block specifically for standard motion blocks and another dedicated to approximate positioning blocks
  4. 4Verify block numbering and ensure referenced blocks are actually of compatible types within the same SYNACT operation
  5. 5Consult the KRL syntax documentation to understand valid variable combinations for your specific block classification
  6. 6Test the reorganized SYNACT instructions sequentially to confirm proper synchronization behavior without mixing incompatible block types

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