In general, PLC and motion control have been separate elements in a machine control application. This has required unique methods to synchronize actions between domains. The significant difference between PLC and motion control domains is that PLC solutions are scan-based systems while motion control systems are event driven. In effect, the application program in a PLC is solved in a highly sequential fashion where the overall scan time dictates the ability of the control system to react to dynamic changes in the I/O system. Gen 3 solutions are now eliminating this distinction by offering real-time event handling to both the motion and logic control domains. At the heart of this innovation is the availability of a machine control language that offers the programming structure to support modularization, dynamic data sharing, and event handling (IEC 61131-3).
The packaging machinery on the market today with the highest return on net assets uses Gen 3 control architectures. Diagnostics, operator ease of use and maintainability are moving to the forefront of the latest packaging machinery. As a result, end users purchasing new packaging machinery are lowering the total cost of ownership. Modern software tools also allow end users to lower the cost of FDA validation, as well. Standardized function blocks for motion have simplified the validation of a machine control solution to meet 21 CFR Part 11 standards.
Machine control software is easier to develop as modularization and extensibility move to the forefront. Modularity and reusability of commercial off-the-shelf software solutions offer machine builders software development methods that facilitate the development of modular machinery. With Gen 3 capabilities lines can be synchronized using networking solutions, and machinery modules can be rapidly integrated in the end user's plant. This same capability is used to synchronize controls across an entire horizontally integrated packaging line. Gen 3 packaging controls give machine builders more time to skillfully deploy solutions that are repeatable from one machine to the next, while allowing a greater amount of time to be spent on adding value from a safety and operational perspective.