Project master scheduling (project MS) allows you to plan long-term demand for parts that are manufactured or purchased, by entering forecasted demand. When project MS is calculated, project master schedule proposals create shop order requisitions and/or purchase order requisitions when the proposals fall within the planning time fence (PTF), if you have indicated that requisitions can be created.
The supply proposals for parent parts created by project MS are broken down and they generate demand for semi-manufactured and purchased component parts, which are input to the project material requirements planning (PMRP) process (or the material requirements planning process, if they are standard planned parts). You may, however, indicate whether the supply for the project MS part should be created by the project MS calculation or not. If you choose not to have supply created by project MS, supply proposals will be created by PMRP based on actual demand, but forecast consumption will take place in project MS.
The project MS calculation considers various parameters and their settings.
If you indicate that rolling should be used, the estimated quantity on-hand development is used to update the project MS proposals after the planning time fence. This means that the first project master schedule proposal after the planning time fence is adjusted by the estimated quantity on-hand development between the run date and the planning time fence. For example, if there is an excess part quantity of 100, it is subtracted from the first project MS proposal after the planning time fence.
The project MS calculation takes any specified lot sizes into consideration. This information is retrieved from the planning data entered for the inventory parts. If the minimum and maximum lot sizes are set to zero, the lot size is unlimited.
Fixed project master schedule proposals remain in existence until the run date, but they do not affect any calculations within the demand time fence. Variable proposals are set to zero (0) so that they can be recalculated outside the planning time fence.
Site level attributes control how project master scheduling plans for a part. The selections that you make in the Manufacturing tab of the Site window determine how the system processes the part during project master scheduling. Selecting the Use Rel Purch Reqs in Planning check box causes project master scheduling to not delete purchase requisitions in Released status at the start of the project master scheduling run. These are viewed as supply, later in the project master scheduling process.
When demand for a part arises, shop order requisitions or purchase requisitions are created from the fixed project master schedule proposals within the planning time fence. Multiple requisitions or schedules will be created depending on the maximum, minimum and multiple values set in the Inventory Part/Planning Data tab. However, this kind of supply is created only if the value in the Proposal Release field in the Inventory Part/Planning Data tab is set to Release, indicating supply for the part is not managed by Kanban circuits.
If you specify that fixed project master schedule proposals are to be created automatically, this happens when the variable proposals fall within the planning time fence. Quantity on-hand development and quantity available to promise are based on the current quantity on-hand minus safety stock.
This is a range of periods, defined for each part, in which the forecast for a part could be consumed for a customer order or a sales quotation. If, for example, the forecast consumption window is set to 5, then when demand is entered for the part, forecasts going back up to five periods from the due date of the demand can be consumed. If further forecast or supply needs to be consumed to satisfy the demand order, then they are consumed outside the five-period window and an action message is generated for the part. Forecast consumption only occurs backwards from the due date of the demand.
The forecast consumption window is always bounded behind the order due period by the demand time fence; this overrides the lower bound in the forecast consumption window, if this has been defined for the part.
If no forecast consumption window has been defined for the part, the lower bound defaults to the demand time fence for the part.