用户继续将PLC与Instant in Instant，高平均时间（MTBF）和高平均时间 - 修复（MTTR）相关联。对可靠性，性能，可重复性和可预测性的声誉继续推动对能够承受恶劣工业环境的简单崎岖系统的需求。
The PLC platform has evolved by incorporating open standard interfaces, multidomain functionality, distributed modular architectures and modern software capabilities integrated as turnkey automation solutions. The label “PLC” simply understates the capability of current automation systems. As a new generation comes to market, the more apt notion of Programmable Automation Controller (PAC) will displace its predecessor. PACs augment the function and role of the traditional PLC by defining new capabilities.
Flexible and configurable, PACs can be customized and optimized to meet the application needs for both machine and plant automation systems. All parts of the PAC are designed to maximize software and hardware integration. A single programming environment and engineering tool provide transparent access for all parameters and functions within the entire system. A single platform can combine PLC, soft logic, remote input/output (I/O), motion control, drives, PID control, user guidance, visualization and data handling. The use of Ethernet TCP/IP, Internet and IT standards maximize data integration throughout the enterprise.
Market Impact
PACS的出现将在重点转向沟通标准和软件集成。用户将更专注于总系统性能而不是硬件选择。PACS将解决用户对监控和控制真实设备的更好程度的担忧。这使PACS的供应商能够更多地思考系统性能，而不是在组件级别的市场差异化。
在协作制造环境中，PAC的多功能功能使得生产过程信息的访问和交换，并将工厂地板运营连接到企业级系统。在传统的PLC产品需要专有的编程语言的情况下，可以使用IT标准命令PAC，例如SQL查询和开放数据传输技术，例如用于过程控制（OPC）和可扩展标记语言（XML）。这提供了更快的实际，未复制，数据的更新，并且消耗最小的带宽，因为企业系统不必轮询控制器。相反，PACS通过事件发送数据。
Outsourced integration
There is an increased dependency on suppliers for services ranging from consulting to full turnkey projects. Users are refocusing their energies on core competencies and relegating many integration functions to their automation providers. This creates a much higher need for service and support offerings that will complement and utilize the multifunction capabilities of PACs. An example of this could be Web-based monitoring and maintenance through a PAC for multiaxis motion control, position control and cam position. Operators can access the supplier’s Web site, allowing technicians to diagnose and troubleshoot problems directly from the plant floor.
Programmable Automation Controllers, or PACs, will play a major role in plant and factory automation by adhering to open industry standards and providing multidiscipline programming and functionality. All parts of a PAC system must be designed to offer end users one programming and engineering tool.
