Finite Capacity Scheduling Instruments

Calculating and working with earliest material availability

The VAPS takes into account the earliest material availability date = EMAD

Material availability: Fundamentals

As of now, we calculate the material availability per production order, meaning on production order level, not on routing line/operation level:
• We calculate a value that we call EMAD
• EMAD = earliest material availability date

Basics of the EMAD calculation

  • We create a unique list of component demand
    • Day by day
    • We take into account
      • Demand from production orders
      • Demand from sales orders
      • Demand from transfer lines
      • Demand from job planning lines
      • Demand from service lines
      • Demand from assembly orders
  • Then we create a unique list of component supply
    • Day by day
    • We take into account
      • Supply on inventory
      • Supply from purchase orders
      • Supply from production orders
      • etc.
  • Then we allocate component supply to component demand

How we allocate

  • First we remove any reservations, because reserved components will never get allocated
  • Then, day by day, we allocate an available component to a
    component demand
  • You can define the priority which demand to supply first
    Example: sales orders first, then production orders, then transfer orders

    VAPS-emad-priority
  • If there is enough component supply on a certain day, we allocate that supply to the component line, and have an earliest material availability date for that component.

Setting the EMAD

  • A production order typically requires multiple components
  • If all components are available in the look ahead window timeframe,
    each component line gets an EMAD
  • We take the latest EMAD of all component lines as the EMAD for the
    production order. Example:
    • Production order 1
      • Component 1 – EMAD = December 1
      • Component 2 – EMAD = November 20 
      • Component 3 – EMAD = December 4
    • EMAD for production order 1 = December 4

Exclude items from EMAD calculation

In the current EMAD calculation logic, “all” components of a production order are considered when calculating the availability date.

With very detailed BOMs and having even low priority material in these BOMs (meaning material which could be replenished very easily e.g. by a local dealer around the corner), this could create some downsides:

  • material that is out of stock but could easily be replenished might render a production order as “unable to allocate”
  • all these materials need to be calculated, although they won’t be a blocker for the production process

Because of this, you can exclude certain items from the EMAD calculation by ticking the option “Exclude From EMAD (VAPS)” on the item card and related pages. You can also exclude complete item categories from EMAD, by ticking the option on the respective category card. In this case, the setting is passed on to all associated articles and does not have to be made separately for each article.

vaps exclude items from emad calculation