Monday, April 12, 2010

SNP PPM Generation With Lot Size Margin

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Function documentation SNP PPM Generation With Lot Size Margin Locate the document in its SAP Library  structure

Use

You use the SNP PPM Generation With Lot Size Margin function to generate SNP production process models (PPMs) from PP/DS PPMs for lot size margins and multiple mode combinations of a PP/DS PPM. Due to the fact that PP/DS PPMs can have multiple modes defined per activity whereas SNP PPMs can only have one mode per activity, the system generates one SNP PPM per PP/DS PPM mode combination.

Integration

It is possible that the number of mode combinations and therefore also the number of SNP PPMs generated will become very large, depending on the number of activities and alternative PP/DS PPM modes. For this reason, there is a different function available that you use before running this function to select certain PP/DS PPM mode combinations or enter parameters in order to restrict the number of SNP PPMs generated. You then flag the chosen PPM plans so that they are considered the next time this function is executed. For more information, see Specifying Mode Combinations for SNP PPM Generation.

You can also run the function described here directly without first defining the mode combinations. Parameters are available on the selection screen for this function, which you use to restrict the number of SNP PPMs generated. However, manual preselection of mode combinations is only possible in the function mentioned above.

Prerequisites

In the system, you have created the appropriate PP/DS PPMs from which you want to generate the SNP PPMs. For more information, see the Structure linkPPM Plan section of the APO master data document.

Note

During generation, the system only takes into account multi mixed resources or single mixed resources that have not been set with the indicator Not SNP Rel. on the Planning Parameters tab page from resource master data. Also, the system only takes into account products with the activated SDP relevance indicator on the Properties tab page within product master data.

Activities

  1. You maintain the control parameters for executing the function. From the SAP APO Easy Access menu, choose Master Data ® Production Process Model ® SNP PPM Generation With Lot Size Margin.

Note

On the selection screen, if you leave the PP/DS plan number and SNP plan number fields blank, the flagged PPM plans and associated control parameters are adopted from the transaction SNP PPM Generation: Determine Mode Combinations. On the selection screen, if you specify a specific PP/DS plan number and SNP plan number, you must also enter the associated control parameters on the screen. If you do not enter any values, the system uses the maximum values possible.

For example, you use the control parameters to specify how the operations, activities, and resource consumption from the PP/DS PPM are transferred to the SNP PPM that has been setup for bucket-oriented SNP planning. You can also restrict the number of SNP PPMs generated by limiting the PP/DS PPM mode combinations considered.

The following control parameters are available:

Parameter

Use

Start Date of Generation Period

You use this date to specify when bucket generation for the SNP PPM plan is to start. The temporary PP/DS order created by the system, from which the SNP plan is to be generated, is also scheduled from this start date on.

If possible, you should choose the start date so that the PPM generation horizon corresponds to a typical horizon for your work processes (based on leave periods, public holidays, and so on).

For generation, it is not possible to shift the start date into the past.

Bucket Size

You use bucket size (period length) to specify which PP/DS plan activities are to become an SNP plan activity during SNP plan generation. To do this, a temporary PP/DS order over a certain lot size (typical order lot size, see below) is created by forward scheduling from the Start Date of the Generation Period specified. All activities from the planned order that fall within a bucket of the pre-specified size, then become one production activity in the generated SNP plan. This means that the longer the bucket is, the more PP/DS plan activities can be included within one SNP plan activity. This production activity is one day long. If necessary, the remaining time from the bucket is occupied by a wait activity.

You should choose the bucket size so that it corresponds to the period length for SNP planning (that is, the period length specified in the planning buckets profile).

Lowest Mode Priority

You use lowest mode priority to specify which PP/DS plan modes are to be considered for the mode combination, that is, how many SNP plans are generated. Modes with a lower priority than the one specified here are not considered for SNP plan generation.

Consumption Calculation

You use the consumption calculation parameter to specify how the variables and fixed bucket resource consumptions from SNP plan activities are to be calculated, which means how the corresponding PP/DS plan consumptions are to be transferred to the SNP plan. There are the following two types of calculation:

  1. Consumption is calculated on a one to one basis, so that one PP/DS order corresponds to one SNP order (generation variant without PP/DS campaign):

The system uses the fixed duration and fixed resource consumption from the PP/DS plan plus the duration of sequence-dependent setup activities to calculate the fixed bucket consumption of the SNP plan. The duration of these activities is calculated as the setup duration of an initial setup group/setup key (as specified in the setup matrix) to the setup group/setup key of the operation considered. Variable bucket consumption is determined from the PP/DS plan variable duration and variable resource consumption.

  1. Consumption is calculated on a many to one basis, so that n PP/DS orders correspond to one SNP order (generation variant with PP/DS campaign):

The system calculates fixed bucket consumption from the duration of sequence-dependent setup activities only (see above). The fixed PP/DS plan durations are made linear and go into the variable bucket consumptions from the SNP plan. Variable durations and resource consumptions are also used to determine the variable bucket consumption.

Typical Order Lot Size

This is the lot size over which the system creates a temporary PP/DS order. The system uses the temporary PP/DS order to assign PP/DS PPM operations to the respective SNP buckets (periods) using normal scheduling rules.

As the order length is usually based on the lot size, you should enter the typical order lot size in this field. When choosing this lot size, it should correspond to the typical SNP lead time, because all orders that you create from the generated SNP PPM receive the duration derived from the temporary PP/DS order.

As a rule, the larger the typical order lot size, the longer the duration of activities in the generated SNP PPM. Note that if you choose an order lot size that is too large, the duration of activities may exceed the bucket size, and the system will not be able to generate an SNP PPM. Because of this, there are several options available for determining the typical order lot size (see the selection help).

Maximum Number

You use this parameter to specify an upper limit on the number of SNP plans to be generated.

If this number is exceeded, the system terminates generation.

  1. You run the function.
  2. The system generates SNP PPMs from the specified PP/DS PPMs according to the parameters you defined.
  3. It is possible to view the results of the function and messages in a log. From the SAP APO Easy Access menu, choose Master Data ® Production Process Model ® SNP PPM Generation: Display Log.
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