Comparing Strategies 56 and 89
Strategy |
Characteristics Planning w/ Dependent Req'ts (56) | Assembly Processing w/ Char. Planning (89) |
Long Term Planning |
no |
LTP scenario |
Components |
No specific strategy group at component level |
Strategy group 70, mixed MRP = 1 |
Creation of planned independent requirements |
Active version |
Inactive version |
Consumption and reduction at header level |
Allocation at configured material level, and indirectly (after MPR), reduction of all components |
No allocation |
Consumption and reduction at component level |
Consumption at component level does not take place; however, requirements for components are indirectly reduced for all components after consumption at header level |
Only components that are used in actual configuration are reduced |
Example for reduction at component level: Planned quantity 100 PC Usage probability of combination value key A = 70% Usage probability of combination value key B = 30% Resulting in requirements for 70 PC of component A and 30 PC of component B |
An order for 20 PC (featuring characteristic A) is entered resulting in: The requirement for the components is changed to: 56 PC (80 PC * 70%) of component A and |
An order for 20 PC (featuring characteristic A) is entered resulting in: The requirement for the components is changed to: 50 PC (70 PC – 20 PC) of component A and |
This leads to the following conclusions:
|
Strategy 56 w/ dependent req. |
Strategy 89 | |
General |
Easier to handle (Batch run after completion of planning, monthly), especially if you cannot plan precisely or if you only want to plan capacity on header level |
More precise planning of components |
Performance |
MRP has to plan customer order AND planning of demands management all the time |
Planning of demands management is done in LTP (typically only in the planning periode, for example a week or month) and independent of MRP |