How To Fix OQ_C420 - Different units of measure defined for child and parent tanks

SAP Error Message - Details

• Message type: E = Error

• Message class: OQ_C - IS-Oil SSR : Message pool Fuels

• Message number: 420

• Message text: Different units of measure defined for child and parent tanks

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message OQ_C420 - Different units of measure defined for child and parent tanks ?

  The SAP error message OQ_C420 indicates that there is a mismatch in the units of measure (UoM) defined for a parent tank and its child tanks in the system. This typically occurs in scenarios involving tank management, where a parent tank (which may represent a larger storage unit) contains child tanks (which may represent smaller storage units).
  Cause:
  The error arises when:
  
  The parent tank is defined with a specific unit of measure (e.g., liters, gallons) that differs from the unit of measure defined for one or more of its child tanks.
  This discrepancy can lead to confusion in inventory management, reporting, and transactions, as the system expects consistent units of measure for proper calculations and operations.
  
  Solution:
  To resolve the OQ_C420 error, you can follow these steps:
  
  
  Check Tank Definitions:
  
  Go to the tank management module in SAP and review the definitions of both the parent tank and the child tanks.
  Ensure that the units of measure for both the parent and child tanks are the same.
  
  
  
  Modify Units of Measure:
  
  If you find discrepancies, you will need to modify the unit of measure for either the parent or child tanks to ensure they match.
  This can typically be done in the tank master data settings.
  
  
  
  Recheck Configuration:
  
  After making changes, recheck the configuration to ensure that all related tanks are now aligned in terms of their units of measure.
  
  
  
  Test the Changes:
  
  Perform a test transaction or operation that previously triggered the error to confirm that the issue has been resolved.
  
  
  
  Documentation:
  
  Document the changes made for future reference and to assist other users who may encounter similar issues.
  
  
  
  Related Information:
  
  Transaction Codes: You may use transaction codes like T_CODE (for tank management) or MM02 (to change material master data) to access the relevant settings.
  Unit of Measure Configuration: Review the configuration settings for units of measure in the SAP system to ensure that they are set up correctly and consistently across all relevant materials and tanks.
  SAP Notes: Check for any relevant SAP Notes or documentation that may provide additional insights or updates related to this error message.
  
  By ensuring that the units of measure are consistent across parent and child tanks, you can effectively resolve the OQ_C420 error and maintain smooth operations within your SAP environment.