SCM Planning Solutions IBP APO Ariba: Restrictions of the Production Planning and Detailed Scheduling (PP/DS) optimizer

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Summary

Symptom
Restrictions of the Production Planning and Detailed Scheduling (PP/DS) optimizer
Other terms
Optimizer, buckets, containers, block tolerances, order creation, warehouse
Reason and Prerequisites
You are using the Production Planning and Detailed Scheduling (PP/DS) optimizer.
Solution

The PP/DS optimizer tries to improve the solution gradually but there is no guarantee that it will find the optimum solution. In addition, the gap in relation to the optimum is not definite.

For releases earlier than SCM 7.0, the following applies: The optimizer does not create any new orders and does not delete any existing orders. It does not create new orders and does not change the production process model (PPM) or lot sizes. Only the dates of the operations are changed. Note 1155421 contains restrictions regarding the creation of orders as of Release SCM 7.00.

For releases earlier than SCM 7.0, the following applies: A finite container planning is not supported. Note 1171154 contains restrictions regarding finite container resource planning as of Release SCM 7.00.

The deactivation of the "Self Reference" indicator from resource networks is ignored by the optimization. Linking a resource to itself is always allowed for the optimization.

During block planning, the blocks are taken into account but the block tolerances are not used.

The optimizer starts with the pegging of the liveCache. Without this pegging, material bases and delays cannot be calculated. Therefore, scenarios without pegging; for example, when you use the rapid prototype matrix, are not supported without the optimizer creating the pegging.

No bucket resources are supported. Operations that use a bucket resource are fixed for the optimizer.

For releases earlier than SCM 5.1, the following applies: Bi-finite planning is not supported. However, it is useful to use the PP/DS optimizer for a finite planning after a bi-finite forecast.

On infinite single-activity resources with setup matrix, the optimization cannot plan the setup activities as sequence-dependent activities. Instead, the average setup times are used for planning.

For releases earlier than SCM 7.02, the following applies: With conti-IO nodes, the material is always allocated to all recipients in parallel. Acceptance with sequencing so that first order A1 and then order A2 continuously accepts from a chronologically overlapping manufacturing order A (that is, A does not end before A2), is not supported. In this case, a finite capacity modeling with discrete IO nodes is to be avoided. Note 1533835 contains information about the functions in relation to conti-IO nodes as of Release SCM 7.02.

The optimization of the order lead time is not part of the optimization goal. Using compact scheduling (available as of Release SCM 5.0) reduces the order lead time in the postprocessing step.

The planned delivery time is only taken into account for purchase requisitions. If a component is missing and if no receipt is planned as yet, the planned delivery time from the product master is not used.

Scheduling agreements are not rescheduled; instead, they are treated as fixed (see Note 666725).

Fixed operations retain their planning/deallocation status.

The optimizer does not support days' supplies. Safety stocks are supported only if they are available as additional requirements.

The "Deallocation with delay" function and the function for deallocation in case of validity violations cannot be linked with campaign planning.

The "Deallocation with delay" function cannot be linked with container resources planning.

The function for taking into account the exact continuous material flow can be linked with campaign planning or time decomposition.

During the campaign optimization with maximum campaign length, the processed campaigns must be completely visible for the optimizer to be able to determine the length. The first orders processed must not be deleted from the system; if they are, the maximum length for the campaign in question may be exceeded.

The campaign optimization is based on the bottleneck resources. There must be no direct or indirect time link (in the form of constraints or material dependencies) between the operations or orders that are planned on the bottleneck resources. In particular, bottleneck resources may be used only once in the production flow.

The explanation log cannot provide the best explanation for all modellings (see Note 840883).

Note 765320 describes compatibility restrictions regarding previous versions.

Header Data


Release Status:	Released for Customer
Released on:	23.12.2010 15:57:59
Master Language:	German
Priority:	Recommendations/additional info
Category:	Consulting
Primary Component:	SCM-APO-OPT-PPS Production Planning and Detailed Scheduling