Next-generation controllers reduce costs, increase productivity
In a challenging economy, it is more critical than ever for plants to increase productivity and deliver cost savings in whatever ways they can. By innovating their processes with new control systems, plant managers can accomplish just that.
Seemingly buried by the daily doses of economic bad news lies the reality %%MDASSML%% perhaps slightly forgotten %%MDASSML%% that periodic downturns are nothing new to manufacturing industries, where cyclical business patterns have always been a given. Although the severity of the current downturn may be greater than previous downturns, it nonetheless represents a powerful opportunity for manufacturers and equipment suppliers to review new approaches in factory automation to provide benefits in both manufacturing cost and efficiency. From that viewpoint, this downturn is no different than others. While some companies will struggle in the coming months, others will thrive with the appropriate and timely integration of innovation into their existing manufacturing processes.
Economics of automation
The core purpose of industrial automation is to apply technology to increase production flexibility and reduce the cost of ownership in a manufacturing or process facility. In a challenging economy, it is even more critical to deliver cost reductions and focus on increased productivity than when strong economic tailwinds are flooding purchase orders through the front door.
The key to achieving these cost and efficiency gains usually starts with the new generations of high-powered programmable controllers %%MDASSML%% now available at far lower costs than those of just several years ago. These controllers serve as the system nucleus to control distributed I/O, collect data and network with other sub-systems or production cells.
Scalability in a control platform allows a close match of processing performance to machine requirements and eliminates any overkill purchase in controller capability. Scalable control systems can range from very small programmable relays to full-blown, high-end PC-based control systems. The combination of low cost and high performance with built-in Ethernet connectivity makes networking smaller machines and production cells more attractive. Today’s new inexpensive programmable controller/relays are designed to control small to midsize machines that require few I/O points. Common features can include Ethernet connectivity, removable operator displays, easy flow chart programming and I/O expansion modules.
On the other end of the spectrum are high-end PC-based control systems . The software running on them accommodates the ever-increasing need for expanded instruction sets, plus seamless support of Ethernet-based I/O networks such as MODBUS TCP, EtherNet/IP or Profinet. Easy programming, fast and comprehensive debugging and seamless integration into HMI software packages are of the requirements for automating a system or process.
Flow chart control software packages offer advantages such as easy reading of the control logic and faster machine troubleshooting %%MDASSML%% especially during startup %%MDASSML%% due to the simple and intuitive nature of flowchart programs. This makes it easy to see where a program may hang up due to an underlying hardware problem or defective machine part. Execution trails help pinpoint possible causes for downtime faster than with other programming languages.
Open system advantage
Driven by the need to improve quality and increase production flexibility, today’s manufacturers sometimes expect turnkey solutions, where software and hardware are all from the same manufacturer. When possible, this can eliminate incompatibilities between hardware and software and allow for faster programming and machine startup. It can also reduce machine design complexity, troubleshooting time and the risk of downtime and lost production. However, in many cases where a “one-stop-shop” solution might be desired, the market realities necessitate the connection of I/O modules or subsystems from multiple vendors. This holds especially true for larger, more complex automation systems where no one vendor has 100% of the needed components.
Interconnectivity between products from multiple vendors was certainly made easier once standardized fieldbus networks such as Profibus, Interbus or DeviceNet found wide acceptance. The emerging trend to use Ethernet-based communication protocols such as Modbus TCP, EtherNet/IP or Profinet to read and write data to devices now allows an additional standardization on Ethernet as the physical layer.
These networks allow machine builders even more flexibility to meet end user requirements. They can also eliminate the need to redesign the entire machine layout from scratch for another customer because the base I/O structure stays the same regardless of which communication protocol is used. Modular I/O structures allow easy connection to input and output signals %%MDASSML%% regardless of whether they are digital, analog or a special function. Selecting an I/O supplier with a wide and flexible range of modular I/O point configurations, network adaptors and special function modules ensures that a custom configuration can be easily tailored to any application and for any Industrial Ethernet network.
Managing demand for data
Requirements for more data exchange capabilities are driven by ever increasing networking of production cells and increased data volumes. Technologies such as vision systems or sophisticated data logging requirements increase data volume that must be collected and pushed over a network to other parts of the machine or factory. Collected data can be used to better analyze and streamline production processes, improve product quality, provide better diagnostics to increase machine uptime and make the production process more transparent through the use of industrial-grade Ethernet infrastructure components.
Industrial Ethernet switches, Power over Ethernet and wireless products are designed to rugged industrial specifications to ensure reliability under the most adverse conditions. Unmanaged industrial Ethernet switches, which require no configuration, are often ideal for small, simple, isolated networks. Managed switches provide a network with the capability for increased traffic monitoring, control and diagnostics.
By assigning an IP address to a managed switch, it can be used to remotely monitor and administer both the network and the functions of the switch. Managed switches support SNMP for compatibility with IT networks and feature easy Web-based management via a simple Web browser. To build robust redundant and self-healing network connections between corporate networks and the factory floor, many managed switches support higher level functions such as Rapid Spanning Tree Protocol or Fast Ring high speed redundancy, IGMP Snooping & Query , VLAN and port security.
The future will bring even faster network speeds and higher utilization of wireless technologies to exchange data with hard-to-reach components or to eliminate physical cable prone to wear and tear. Wireless technology is also perfectly suited to bridge larger distances to remote sites or between large buildings where physical cabling is cost-prohibitive or virtually impossible.
Ultimately, the combined integration of next generation controllers, software, Ethernet infrastructure and I/O result in a lower cost, more efficient and more powerful solution for the factory floor. While the current economic climate presents a challenge to all businesses, it is worth remembering that delivering such productivity gains and cost reductions has always been the challenge that innovative industrial automation systems are designed to overcome.
Greg Dixson is a product marketing manager and Bjoern Falke is a lead product specialist. Both Dixson and Falke work for Phoenix Contact Automation Systems.