Perform Site MRP
Explanation
This activity is used to calculate supply and demand for MRP planned parts, based on existing shop orders,
customer orders, etc. The system creates MRP-planned proposals for fulfilling these demands, such as purchase or
shop order requisitions. It also creates suggestions to replan existing supply orders, considering projected
material availability.
Planned supplies and action messages generated in previous MRP processes will be removed as first step in the
calculation.
More detailed descriptions of Material Requirement Planning can be found in following documents:
About MRP
About messages from MRP
About the phases of MRP
About Alternate Components in MRP
Prerequisites
- BOMs must have been defined for the parts, and lead times for both purchased and manufactured parts must have
been established. MRP only uses the existing product structure with the alternate " * " indicated
by an asterisk(*).
- To perform MRP for master scheduled parts you must first have created a master production schedule using
IFS/Master Scheduling.
- To perform MRP for project planned parts you should first run PMRP.
- To perform MRP for DDMRP buffered parts must have been positioned using the planning method H, also buffer
zones and buffer levels must have been established.
Note: MRP does not process parts with planning methods B - Order Point Planning, C - Replenishment Level,
M - Manufacturing Cell Part or N - Next Level Demand.
System Effects
- After this process is executed, the Warning or Error status can apply. Error indicates that some critical
errors have occurred in the process, and the MRP process has stopped. Warning indicates that a message posted for
this process has to be reviewed by the user. This can be done by using the Show Details
command on the Background Jobs page, which displays the message in the status information table. If
the user decides to continue the MRP process, the MRP process will display error messages when the process is
completed.
- MRP calculation will consider inventory parts for which the MRP Control option is enabled on
Manufacturing tab on the Inventory Part page.
- MRP will generate shop order requisitions or non-firm production schedules for parts that are defined as
manufactured, and it will generate purchase requisitions or supplier schedules for parts that are defined as
purchased. For parts defined as remanufactured it will generate shop order requisitions.
- Shop order requisitions and purchase requisitions that are not converted into shop orders or non-firm
production schedules will be deleted upon starting the next MRP process. MRP calculates the lowest level code of
parts and updates the Low Level on the Inventory Part/Manufacturing tab.
- For buffered parts (using planning method H, Buffered Part) MRP planned supplies are created without
considering future demands but considering open supplies, on hand quantities, demands due today, past due demands
and qualified order spikes. Qualified order spikes are demands that fall within the order spike horizon and which
equal or exceed the order spike threshold.