Master production scheduling


The master schedule (or master production schedule or MPS) sets the quantity of each end item (finished product) to be completed in each time period (week or month or quarter) of the short-range planning horizon.

Master production schedules (MPS) are developed by reviewing market forecasts, customer orders, inventory levels, facility loading and capacity information regularly.

The MPS is a plan for future production of end items over a short-range planning horizon that usually spans from weeks to several months. It is an important link between marketing and production.

Objectives of Master Production Scheduling

1. To schedule end items to be completed promptly and when promised to customers.
2. To avoid overloading or under-loading the production facility, so that production capacity is efficiently utilized and low production costs result.

Translating aggregate plans:

The aggregate plan sets the level of operations that roughly balances market demands with the material, labor and equipment capabilities of the firm. The aggregate is translated into specific number of end products to be produced in specific time periods. Products are grouped into economical lot sizes that can realistically load the firm’s facilities. The MPS represents a manufacturing plan of what the firm intends to produce and not the forecast of what the firm hopes to sell.

Evaluating alternative master schedules:

Master scheduling is done on a trial and error basis. Trial-fitting of alternative MPS can be done by simulation using computers. Detailed material and capacity required are then derived from the firm’s MPS.

Generating material requirements:

The MPS is the prime input to the MRP-1 system. The MRP-1 system provides for purchasing or manufacturing the necessary items in sufficient time to meet the final assembly dates specified, based on the MPS for end products.

Generating capacity requirements:

Capacity needs, arise for manufacturing the components in the required time schedule to meet schedule to meet the requirements of end products as per the MPS. Capacity requirement planning is based on the MPS which should reflect an economic usage of labor and equipment capacities. Master schedules will have to be revised when capacity requirements are inadequate.

Facilitating information processing:

By controlling the work load on work centers, the MPS determines the delivery schedules for end products both for make-to-stock and make-to-order items. MPS also co-ordinates management information such as marketing capabilities, financial resources for carrying inventory and personnel policies for supplying labor.

Maintaining valid priorities:

The absolute or relative priorities for various jobs to be completed reflect the true needs. This means that, the due date and the ranking of jobs should correspond with the time the order is actually needed. When customers change their orders or materials get scrapped sometimes, either the components are not actually needed or the end items cannot be produced because of shortage of some materials and then it is necessary that the MPS should be modified to reflect this change.

Effectively utilizing the capacity:
By specifying the end item requirements over a time period, the MPS establishes the load and utilization parameters for labor and equipment (i.e. shifts worked or overtime or idle time).