Workload control, to compute planning priorities

If the desired production volume for a plan period exceeds the capacity or material constraints, LN must make a selection. Some plan items can be planned immediately. The rest must be moved to the next or the preceding plan period.

This selection is based upon the following planning data and item data:

Planning data:

  • Production volume
  • Volume moved
  • Numbers of periods moved

Item data:

  • Total material costs
  • Production costs
  • Item priority

Item data can be defined in the Items - Planning (cprpd1100m000) session.

You can change the planning priority calculation in the Work Load Control Parameters (cpwlc2101m000) session. The effects of the fields in that session are demonstrated in the Workload control, a detailed example topic.

  • Priority Level

    A priority level is calculated for each plan item. Three different approaches are available. The priority level can be based on:

    • Planning data, such as the production volume
    • Predefined item priorities (such as high, medium, low)
    • A combination of planning data and item priorities

    Determine this by setting the Consider Item Priority field.

  • Planning data

    If the Consider Item Priority field is No, the priority level is based on planning data such as the production volume.

    The priority level is calculated according to the following method:

  • Backward/forward planning rules

    First, the priority level is set to one of the following:

    • Production Volume The production volume is the quantity to be produced in a plan period.
    • Volume Moved The volume moved is the production volume that has been moved to another plan period.
    • Number of Periods Moved The number of periods that a certain production volume has been moved backward or forward.
    • Volume and Periods Moved The Volume and periods moved is defined as:
    Volume moved * Number of periods moved

    Separate rules for the backward and forward planning steps can be defined in the Backward Plan. Rule and Forward Plan Rule fields.

  • Material and Production Costs

    The priority level that was determined in the previous step, can be adjusted by multiplying it by the material or production costs of the plan item. This is determined by the Consider Material Costs or Consider Production Costs in the Work Load Control Parameters (cpwlc2101m000) session.

  • Predefined item priorities

    If the Consider Item Priority field is set to Only, the priority level is based on predefined item priorities. Item priorities can be low, medium, high, and so on. The priority of each plan item is recorded in the Priority field in the Items - Planning (cprpd1100m000) session.

  • Combination of planning data and item priorities

    If the Consider Item Priority field is Yes, the priority level is based on a combination of planning data and predefined item priorities.

    The priority level is subsequently multiplied by a priority factor which reflects the relative importance of a plan item. The priority factor is based on the following table:

PriorityPriority Factor
Highest1.8
Very high1.6
Higher1.4
High1.2
Medium1
Low0.8
Lower0.6
Very Low0.4
Lowest0.2

 

The priority of an item is recorded in the Priority field in the Items - Planning (cprpd1100m000) session.

Note

The unit of measure is not considered in the criterion of production volume. If the plan items are measured in a number of different units, such as piece, kg, or liter, the production volume is not a suitable criterion. In that case, it is better to use the financial value of the production volume. Do this by selecting the Consider Material Costs or Priority check boxes.

If the planning rules result in the same priority level for two items, the item with the highest production volume is planned first.

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