Master Scheduling

Master scheduling plans groups of parts (MS level 0) to end item (MS Level 1) parts. Level 0 refers to the top level plan group which collectively represent parts with similar design. Level 1 parts represent the end items, or tangible items or the items that are at the lowest level of the planning structure. In between Level 0 and Level 1 parts there can be MS phantom parts (order code T) which can be used for sub grouping of parts with similar design. Level 0 parts, Level 0 phantoms, and Level 1 parts will be defined in IFS Applications using MRP order code O, T and A respectively.

Note: If project master scheduling is used, then a project planned netting group will be attached to a Level 0 and Level 1 part and considered as planned using project master scheduling (project MS).

A Level 0 part is a form of a blow-through part and cannot have a balance on hand or be ordered. Disaggregation of Level 0 parts will yield Level 1 parts for master scheduling. They are the parts which are planned by MS Level 1.

Even though master scheduling can start at the Level 0 part family, it can also start directly by planning level 1 forecasts for Level 1 parts in the MS Level 1 Part window. Master scheduling Level 1 parts can be distinguished from project master schedule Level 1 parts as project master schedule has a project PNG value and master schedule has the value * for project PNG.

When MS level 1 is calculated, 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 MS are broken down and they generate demand for semi-manufactured and purchased component parts, which are input to the project material requirements planning (project MRP) process (or the material requirements planning (MRP) process, if they are not project master scheduled parts). You may, however, indicate whether the supply for the MS part should be created by the MS calculation or not. If you choose not to have supply created by MS, supply proposals will be created by project MRP based on actual demand, but forecast consumption will take place in MS.

Note: In IFS Applications, project MS and MS features are executed in the same windows by separating them with the PNG value (If the value for the PNG is *, master scheduling is used and a unique ID must be given for the PNG if project master scheduling should be used)

Important Parameters for MS Calculation

The MS calculation considers various parameters and their settings.

Rolling

If you indicate that rolling should be used, the estimated quantity on-hand development is used to update the MS proposals after the planning time fence. This means that the first 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 MS proposal after the planning time fence.

Minimum, Maximum and Multiple Lot Sizes

The 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.

Important Details for MS Calculation

Fixed 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 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 master scheduling. Selecting the Use Rel Purch Reqs in Planning check box causes master scheduling to not delete purchase requisitions in Released status at the start of the master scheduling run. These are viewed as supply, later in the master scheduling process.

When demand for a part arises, shop order requisitions or purchase requisitions are created from the fixed 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 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.

Forecast Consumption Window

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.