Yield type and quantity extra

Quantity Planned Rejects

The quantity extra is used to account for the product quantity that has disappeared in the operation, due to a limited yield. This is especially important when an operation is reported completed, in case the quantity completed must be automatically calculated.

If the yield type is Discrete, the quantity extra is zero by definition.

If the yield type is Continuous, the quantity extra is calculated from the scrap and yield of the operation, the planned quantity, and the quantities completed and rejected.

Note: The value of the Planned Scrap field increases proportionally with the sum of the Completed and Scrapped fields. The scrap quantity, however, is added to the quantity extra immediately when the operation is started.

Formulas

The Planned Scrap field is calculated according to the following formulas:

Quantity Extra = OP x QLY + SQ
  • OP: Operation progress
  • QLY: Quantity expected to be lost due to limited yield
  • SQ: Setup Scrap (of the operation)

The operation progress is defined by means of the following formula:

OP = (QC + QR) / QPO
  • OP: Operation progress
  • QC: Completed
  • QR: Scrapped
  • QPO: Quantity Planned Output 
QLY = (1 - YP/100%) x (QPI - SQ)
  • QLY: Quantity expected to be lost due to limited yield
  • SQ: Setup Scrap (of the operation)
  • YP: Yield Percentage
  • QPI: Quantity Planned Input