Determining Component Qty and Requirement Dates during MATP 

Purpose

For the multilevel ATP check (MATP), Production Planning and Detailed Scheduling (PP/DS) must determine the component quantities and the component requirements dates for products that are produced in-house. This process describes how the system determines this data by selecting a plan (PPM, iPPE process structure or runtime object), exploding the plan and then subsequent scheduling.

Process Flow

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       1.      The system selects a plan for the product, using the relevant requirements quantity and requirements date, and then explodes the plan for this requirements quantity (lot-for-lot quantity). If you are planning with assembly scrap, the system explodes the plan with a correspondingly higher product quantity.

A relevant requirements quantity is

·         The open requirements quantity for the product, in the first step of the multilevel ATP check

·         A partially confirmed quantity or a fully confirmed quantity for the product, in the second step of the multilevel ATP check

For more information, see Multilevel ATP Check in Two Steps.

       2.      The system uses the product quantity to calculate the required component quantities. If you are planning with activity scrap, the system increases the component quantities accordingly.

       3.      The system uses the product quantity and, if necessary, the activity scrap, to calculate the capacity requirements of the activities.

       4.      To determine the component requirements dates, the system executes scheduling for the activities, according to the following system-internal defaults:

¡        The system uses the production calendar for the location.

¡        The system uses the modes with the highest priority for the activities.

¡        The system schedules the activities infinitely on the resources; that is, the system does not consider existing resource loads.

¡        The system does not consider the resource blocks.

¡        For sequence-dependent setup activities, the system uses the setup activity durations calculated during the plan explosion, not the sequence-dependent setup duration from the setup matrix.

¡        The system uses the planning-related minimum interval for the time relationships between the operations, not the process-related minimum interval.

If you plan a product with a PPM or an iPPE process structure, you define the planning-related minimum interval for a relationship in the plan. The planning-related minimum interval must fulfill the following conditions:

process-related minimum interval £planning-related minimum interval £ maximum interval

If you are planning a product with a runtime object, the system determines the planning-related minimum interval using routing data from the ERP system.

This type of scheduling largely corresponds to lead time scheduling in the ERP system.

Result

The component quantities and component requirements dates of the product are determined. Using this data, the ATP check can check the availability of the components. For continuous component consumption, the ATP check assumes that the earliest date on which a component will be required is the requirements date for the total component quantity.

After the system has executed this process down to the lowest BOM level, on a multilevel basis if necessary, a correlation calculation occurs in which the system determines the quantity of the end product that can be produced using either the available components or the components that can be produced. Thus, the least (or latest) available component determines the quantity (and completion date) of the end product and the other components. The quantity that is required by a component can be less than the quantity that is determined during the original plan explosion. If necessary, after the correlation calculation, the system performs a plan explosion with the smaller quantity to check the validity of the plan and adjust the component dates. This step does not, however, optimize the originally-calculated completion date of the finished product.