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SIMATIC IT Preactor APS, now part of Opcenter, improves synchronization of manufacturing processes through robust planning and scheduling tools. It enables increased resource utilization and on-time delivery, while also helping to reduce inventory levels and waste.

Man at computer reviewing a manufacturing plan using Siemens Preactor APS software

Preactor APS is now part of Opcenter

Preactor Advanced Planning and Scheduling (APS) Software

SIMATIC IT Preactor APS, now part of Opcenter, improves synchronization of manufacturing processes through robust planning and scheduling tools. It enables increased resource utilization and on-time delivery, while also helping to reduce inventory levels and waste.

Enabling manufacturers to easily generate plans and schedules and then react quickly and intelligently to changes, Preactor APS software represents a pillar of Siemens’ manufacturing operations management (MOM) portfolio. Along with a manufacturing execution system (MES), quality management software (QMS), and manufacturing intelligence, SIMATIC IT Preactor APS make up a holistic MOM solution that links enterprise software solutions with manufacturing floor automation.

Now under the Opcenter APS umbrella, Preactor APS includes systems tailored to specific functional needs. SIMATIC IT Preactor Advanced Scheduling (AS) is used to schedule machines, production lines, resources, services, and logistics. Preactor AS is offered in multiple versions to meet the specific needs of each customer, including Preactor AS Standard, Professional, and Ultimate. SIMATIC IT Preactor Advanced Planning (AP) aids manufacturers in long- and mid-term planning for both make-to-stock and make-to-order operations. SIMATIC IT Preactor Express is free to use the edition of the Preactor family of production planning and scheduling solutions. All these systems are discussed in greater detail below.

Preactor software functionality

Preactor APS uses advanced math to analyze and calculate achievable production schedules, taking into account a range of constraints and business rules. This approach enables planners to generate and evaluate multiple scenarios. Without such powerful tools, manufacturers may use hours or even days to generate schedules using spreadsheets. These are difficult to maintain, and if an unexpected change occurs, it is difficult to generate a new schedule.

Preactor can be customized and configured as needed without disturbing core Preactor code. It can be used as a standalone system or integrated with enterprise and MOM software, including ERP, MES, data collection, forecasting, demand planning, and OEE applications.

Key features of Preactor APS software include:
  • BOM-level planning—The planning bill of materials (BOM) can be exploded, and then the production plan for lower level items is calculated in the same way.

  • Order-based multi-constraint scheduling—Users can apply a ranking or weighting to orders. Scheduling is created based on resource availability, additional constraints and materials required for the order.

  • Advanced constraint modeling—Rules about concurrent rule usage, advanced interoperation constraints and other advanced resource constraints can be modeled.

  • Advanced material handling—Custom rules can be implemented to ensure that sub-assemblies and raw materials are consumed according to business rules. Material allocation is determined based on system filters and ranking of data.

  • Advanced schedule optimization—Additional rules enable the minimization of changeover times and other schedule-optimizing actions.

  • Assembly process visualization—Material explorer generates a graphical view of material dependencies as well as plots of stock levels over time.

  • Interactive schedule visualization—Once an initial master production schedule (MPS) has been created, data can be displayed as stock profile graphs and capacity usage graphs. The MPS can be changed by simply clicking and dragging a point on the stock or capacity graphs, and the production of a particular item can be moved from one planning period to another. Any changes are reflected in all linked plot and grid windows.

Preactor AP advanced planning software

SIMATIC IT Preactor AP advanced planning software is an essential planning tool that enables manufacturers to ensure they have the right amount of resources in the right places at the right times. Effective purchasing of economic quantities of raw material and timely use of this raw material is key to reducing one of the greatest production problems: unnecessarily high stock levels of both finished product and raw materials, and the possibility of this stock reaching its sell-by date before being consumed.

With Preactor Advanced Planning, planning can be executed in finite or infinite capacity mode, and planning time periods can be days, weeks, months, or a combination of all three. Parameters can be set against each item code, which allows for different calculations for each of them.

Used in combination with Preactor Advanced Scheduling, Preactor Advanced Planning can receive detailed production scheduling information and override planned volume with scheduled volume. The master production schedule (MPS) can then be recalculated using the production schedule as the basis for new results.

For make-to-stock operations, the primary driver in creating the MPS is typically the forecast of future demand. Unfortunately, forecast demand may vary greatly because of seasonality, promotions, weather, special events, and other factors. To avoid creating an unrealistic MPS in which there is not enough production capacity to meet peaks in the forecast, Preactor Advanced Planning imports current stock levels plus actual and forecast demand. It then considers rough-cut capacity, packs forward figures, target days of stock cover, manufacturing preferences, minimum/maximum re-order quantities, re-order multiples, product shelf life, and more to propose an accurate and achievable MPS. By using the Preactor AP calendar system capacity, production capacity (which can be specified by quantity, duration, or weight) can be varied over time. The capacity available then limits the production volume created in each period.

Once an initial MPS has been created, the data can be displayed as both stock profile graphs and capacity usage graphs. These graphs are interactive, and any change made on one is reflected in all other linked plots and grid windows.

In a make-to-order environment, the stock levels of finished and/or intermediate items will not be part of the key process parameters, but there will still be the need to evaluate the effects of future demand changes on the manufacturing process. Preactor Advanced Planning meets this need. For example, for complex assemblies in the aerospace sector, each finished item may have a deep BOM and be made up of thousands of individual components. If many of these components are manufactured in-house, they share production capacity, creating a complex relationship between manufacturing capacity and demand.

When a change in demand occurs, whether that be in terms of quantity or delivery dates, Preactor AP is able to quickly assess if it is possible to meet the new requirements. Preactor AP can import demand changes and create a new ‘what if’ plan. The planning BOM can be exploded so that Preactor AP shows if there are any capacity issues. If there are issues, users can work interactively with Preactor AP to create an acceptable MPS.

Preactor AS advanced scheduling software

A range of Preactor AS products was created to make advanced functionality available to all users. The entire range supports interactive multi-constraint scheduling. Each product ensures an accurate model of the production environment by taking into consideration during the scheduling process the availability of resources and additional constraints, such as tooling and materials. Orders can be scheduled quickly using intelligent built-in rules. Users can also manually interact with the schedule to make changes based on experience or on new information.

Preactor AS Standard uses order-based scheduling to which the user can apply a ranking or weighting to prioritize orders. Preactor AS Standard can take into account different operation run speeds on different resources, use sequence-dependent changeover times based on operation attributes, and allow overlaps and slack time between operations.

Preactor AS Professional offers additional schedule optimization rules to address needs such as minimizing changeover times, preferred sequencing, and campaigning. Composite rules can also be built with Preactor’s workflow tool. Preactor AS Professional enables users to implement customer-specific rules about how materials are consumed. It also provides visualization of production processes from raw materials through to finished goods and sales orders through the system’s material explorer module. This shows a graphical view of material dependencies as well as plots of stock levels over time. The user can see where shortages may occur and choose to keep them as a constraint or ignore them. Preactor AS Professional can also model advanced resource constraints and advanced inter-operation constraints, including limits on the time between operations and how much operation times can be extended.

Preactor AS Ultimate includes a developer license, enabling users to access the Preactor system’s full flexibility. The database schema can be altered as required, including the addition of tables and fields. Via Preactor programming interfaces, it is possible to create custom scheduling rules to solve specific scheduling problems, and to create custom data manipulation tools for use with the Preactor workflow engine. Siemens Preactor also offers Preactor AS Ultimate Viewer, which allows interaction with a Preactor AS Ultimate schedule but does not save any changes. Preactor AS Ultimate customers have used the viewer to provide up-to-the-minute schedule visibility to sales, management, shop floor personnel, cell supervisors or machine operators.

SIMATIC IT Preactor Express

Preactor Express is a free to use edition of the Preactor family of production planning and scheduling solutions. This version allows users to start reaping the benefits of Preactor with the security of knowing that if their planning and scheduling requirements become more involved, they can simply upgrade to one of the other SIMATIC IT Preactor solutions.

Preactor APS benefits

The process of production scheduling and planning can be a daunting task, and more so as manufacturing companies grow and their product lines and resources increase. While each company has its own set of needs and desires for optimum production planning, manufacturing scheduling software offers vital benefits to all users.

Additional benefits:

  • Optimization of production operations

  • Reduction or elimination of non-value-added activities (e.g. setup or wait time)

  • Reduction of late deliveries due to manufacturing delays

  • Alerts for when demand exceeds the capacity

  • Lower production costs

  • The ability to plan for future capacity requirements

  • Less overhead due to more reliable management of scheduling changes

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