Optimizer plans safety stock for distribution demand doubling safety cover
We have a situation that is easy to solve using standard MRP but we are struggling to find a solution for in the SNP optimizer and I'm hoping someone here may be able to help.
We have a manufacturing plant that has it's own warehouse and distributes stock directly to the customer. It also manufactures the same product for distribution to the customer via external warehouses.
All warehouses that supply to customer need to hold a safety stock to ensure that customer demands can be met. This is a time-based safety stock so future demand is automatically taken into account.
The issue that we have is that the external warehouses are holding a safety stock (as expected) and raising purchase requisitions against the manufacturing plant (as expected). The manufacturing plant is then taking these purchase requisitions into account when calculating it's own safety stock and therefore holding stock not only to cover 2 weeks of customer demand, but also the requisition demand from the external warehouses. This means that we are in fact holding double safety stock for any demand through the external warehouse (i.e the expected 2 weeks cover at the distribution site, and a further 2 weeks at the manufacturing site.)
In standard basic ECC planning this is not a problem as on the MRP2 tab for the plant / material there is a safety time indicator that lets you ser a safety time against all requirements or only for independent requirements. Where is the equivalent for the SNP optimizer?
I did find a post from 2009 that relates to this and makes hint of a parameter that could possibly be used to achieve this (GLOBALSAFETYMETHOD) however I can't find any further info on this parameter.
Thanks in advance for your assistance with this,