Understanding MPS Generation for Repetitive Items
When you run the MPS - Net Change version or the MPS - Gross Regeneration version of the MRP/MPS Requirements Planning program (P3482), the system:
Evaluates selected information.
Performs calculations.
Generates a time series and messages for the selected items.
To generate the master production schedule for repetitive items:
Set the processing options to generate the master production schedule.
Enter the type of rate schedule that you want to use for processing.
Set the appropriate processing option to extend rate adjustments to lower-level items.
After you generate a master production schedule, use MPS Time Series and MRP/MPS Detail Message Revisions to review the time series and messages that the system has generated.
The time series is a record of time-phased supply-and-demand netting for selected items. The system links the planned order releases for the parent item to the gross requirements of component items.
If a component does not have its own rate schedule, the system applies the demand from the parent item. The demand from the rate-scheduled parent follows the same logic as regular work orders. When a rate schedule is added for a component of a rate-based parent, the calculation includes the information for the component in both the rate schedule (+RS) and unadjusted rate schedule (+RSU) data lines. The component is processed as supply, and regular MRP logic applies.
The messages reflect how the system uses rate-scheduled items to generate quantities for net requirements for each time period. The MPS/MRP program produces three main action messages that pertain to repetitive items:
Message |
Description |
|---|---|
I = Increase rate to |
Updates an existing rate to the increased quantity. |
H = Decrease rate to |
Updates an existing rate to the decreased quantity. |
N = Create rate |
Treats messages as a group from the MPS/MRP Detail Message Review form. You can answer more than one message at a time. Instead of creating a single rate for a given schedule period type over a date range, the system creates a series of rates to cover the entire period. For instance, instead of having one weekly rate in effect for four weeks, the system creates four weekly rates, each in effect for a week. When you process a Create Rate message, the system can attach the parts list and routing automatically. |
When the system processes messages to update rates (I and H messages), it does not validate the dates that are received. The MPS/MRP regeneration produces messages with valid dates. However, you can change these dates before processing the message. To avoid updating invalid rates, ensure the validity of the dates that you enter whenever you change message dates before processing.