Master Scheduling

The production plan represents a firm’s aggregate measure of manufacturing output. Once this plan is made, it is the responsibility of marketing to sell it and production to implement it. To do so requires a desegregation of the production plan into individual products. The master production schedule (MPS) is a statement of how many finished items are to be produced. Typically the master schedule is developed for weekly time periods over 6-12 months horizon.

Master scheduling is generally a complex problem, especially for products with large number of operations For example, in Dow Corning there are 12 MPS; who are responsible for scheduling 400 packed products over a 26-week time horizon. In process industries with only a few different operations, master production scheduling is somewhat easier.

Master scheduling is the highest level in the medium term scheduling of production goals. It also incorporates materials requirements planning, also known as MRP. Master scheduling addresses the number of units that need to be produced in a defined period. In doing this, it’s important to know what materials are required and how many financial and human resources need to be allocated to produce the designated number of units. Master scheduling breaks down the master plan so that the company knows the number of units it has to produce in a certain period, and what resources will be required to produce them.

Using the Master Schedule: Master scheduling can be a complicated process. Let us summarize some of the observations.

• First, the master production schedule should relate to the aggregate products.
• Second, rough-cut capacity planning assists the master scheduler in developing a feasible schedule by determining potential production bottlenecks. Often, the master scheduled must be revised several times until it is feasible.
• Third, other ways of evaluating a master production schedule include the and cost of setups or product changeovers and short-term inventory fluctuations.

The master schedule is important, since it forms the basis for future production planning activities. Therefore, it must be adaptive to changes in the environment. Seldom will forecasted demands be realized or production plans be adhered to perfectly. As each week passes, operations managers must compare scheduled production with actual results. This may result in changes to the MPS-master scheduling is a full time job! Too many changes, however, indicate that master scheduling is not being performed correctly and can result in poor productivity and low levels of customer service.