Though there is plenty of hyperbole that often goes along with claims of ubiquitous data streams and winning business strategies making the Internet of Things (IoT) ready for liftoff, a tremendous standards foundation has actually made IoT ready for manufacturing applications. Automation associations and their relentless pursuit for interoperability standards for 30+ years have positioned suppliers to reap the full benefits Industrial IoT (IIoT) sooner rather than later.
One organization that’s been pivotal in moving plant data from the control level to enterprise layers over the years has been the OPC Foundation. The foundation’s Unified Architecture (UA) open communication standard is providing plant managers with the ability to make business decisions quicker, a key component to the promise of IIoT.
This is enabled through the standard’s flexibility and ability scale to many manufacturing levels because of its multiple code options, including Java, ANSI C/C++ and Microsoft .NET code.
“OPC UA provides multi-platform capabilities, so you can have either a client or a server on different platforms with many types of applications,” says John Harrington, director of product management at Kepware Technologies. “It could include a Linux, VxWorks, embedded or even FlexSoft Windows application.”
Manufacturers are embracing the standard’s ability to implement OPC in a non-Microsoft environment, along with its enhanced signing and encryption of all messages for better security assurances. These security upgrades have eliminated callbacks and the use of DCOM for remote connections.
OPC UA’s extensible data stack and ease of setup are permitting manufacturers to push service as a solution directly to the controller via manufacturing execution systems (MES) to drive plant efficiencies.
Automaker needs more than messaging
One place where OPC UA is attracting interest is from global automakers and their legacy plants. Market dynamics have changed dramatically for carmakers and they’ve trimmed their manufacturing fat since the global recession and focused on common automobile platforms, which produce multiple car models in one plant.
With the car industry’s restructuring, a global automaker with more than 50 vehicle assembly operations decided to realign its plant floor communication and move away from custom drivers and network card communication that connected to hundreds of PLCs on the plant floor.
“They had a real confusion of connectivity. And by changing their MES and going with an OPC UA-enabled communication platform, they were able to reduce all that complexity,” Harrington says. “A big driver to this change was OPC UA’s ability to communicate to Linux.”
The setup leveraged Kepware’s KEPServerEX communication platform and let the automotive OEM focus on communication rather than new hardware or PLC logic. The carmaker adopted a Linux-based solution because its IT platforms were based on that operating system.
Led by its IT department, the company modified its mainframe MES to connect to its Linux-based business intelligence applications. In effect, its MES expanded to a “services within manufacturing” application and also moved past single-function messaging transactions to the plant floor; it became a bi-directional conversation via OPC UA.
An OPC gateway server, located between the MES and control platforms, now communicates natively to multiple PLCs that support robots, conveyors, welding and fluid fills, to name a few. The carmaker’s previous architecture emphasized redundant PLC messaging to guarantee there was a good connection and ensure quality manufacturing. This continued with OPC UA.
Working with the Java-based OPC client, the MES doesn’t know if it’s talking to a PLC, PC or device. For example, a weld controller in a body shop could see a new vehicle enter its workstation and push a request to the OPC server to identify the options for how to weld this particular vehicle together. The company’s MES uses both Linux and Windows PC in its operation.
After the OPC UA server routes this message to the MES, it will send another message to the PLC to tell it not to resend the request, keeping the welder in a holding pattern. For the automaker, this new communication alignment guarantees delivery of messages, such as recognizing car types and the type of weld that should be done.
Even with increased messaging between the control and MES, this new process actually improves the response time at each platform by 4x compared to the previous communication platform. It also provides a high level of security for the automaker through encrypted messages, application instance certificates, and user authentication on the application level side.
“Manufacturers are adopting OPC UA due to many drivers, but security is at the top of the list, while moving data from the operations side to enterprise,” Harrington says. “OPC UA moves away from DCOM, which could restrict data exposure to other networks outside your local network.”
The autonomy between plant floor and enterprise, allowing for changes to be made without affecting each other, was another huge benefit cited by the automaker.
Production meets monitoring
Contract manufacturers rely on system efficiencies to meet customers’ production goals, along with real-time data monitoring requirements coming from third parties. Southwest Baking recently significantly improved its monitoring capability for the 4.2 million breadsticks it produces weekly.
Southwest Baking’s 40,000-square-foot facility in Tolleson, Ariz., runs production 24 hours a day for five to six days a week, producing large volumes of frozen goods. The production line can produce up to 500 pieces a minute. True to the contract manufacturing industry, this is all done with a lean business model and requires an “all hands on deck” monitoring mindset, from management down to field technicians.
“We can’t all be on the floor at the same time, so we need to monitor real-time data whether we’re in the plant or anywhere in the world,” says Rob Wroblewski, plant engineer at Southwest Baking.
This contract manufacturer picked a KEPwareEX server with OPC UA capability to retrieve vital control data from many types of equipment, such as freezers, mixers and processing platforms. The information is displayed through Opto 22’s groov mobile control and monitoring platform.
With Southwest’s previous configuration, operators spent large amounts of time adjusting inputs to multiple control platforms while not easily seeing the outputs because of a centralized monitoring structure. It meant a lot of wasted time walking from the plant floor to office monitors.
“Now, Southwest Baking has a big panel on the floor with key performance indicators (KPIs) for all the control platforms in the factory,” Wroblewski says. “Do the mixers have the correct weight? Is the freezer and dough at the right temperature?”
This monitoring platform communicates real-time data via large panels on the plant floor, but also on smartphones and tablets. Operators and plant personnel with the proper logins can access the data via any modern web browser.
“However, we didn’t want people controlling the process from smartphones and tablets, even though the monitoring platform lends itself to an HMI control setup,” Wroblewski says. “We also configured floor displays and devices to show different monitoring data for different groups, such as production and engineering pages.” The monitoring platform provides permission layers for different data pages.
Southwest Baking’s monitoring platform uses open standards to monitor data from anywhere, such as HTML5, CSS3 and SVG. Mobile devices need at least Android 4.0.1 (Ice Cream Sandwich), iOS5 or Surface Windows 8. The production monitoring panels display simulated gauges along with numerical data.
An OPC UA server connects to the plant’s various platforms, such as packaging, production and processing platforms, and retrieves data via Ethernet. Opto 22 software polls the OPC tag server every second and then shows live data in blue text on the monitoring screens and mobile devices.
The plant’s six control architectures include many different suppliers, such as Mitsubishi Electric, Opto 22 and Rockwell Automation, and most configuration challenges were minimal due to Ethernet and OPC interfaces. The biggest architecture challenge was a serial controller running RS232 data that required an adapter from the OEM.
According to the contract manufacturer, a junior tech on the operations team configured the monitoring screens quickly. “We literally took it out of the box and had a screen up within an hour,” Wroblewski says. “Drag-and-drop screens come from the monitoring platform’s library and then you customize it with your parameters. More software should be like that.” In total, Southwest Baking has about 12 KPIs, including weight measurement and average length parameters for its baked products.
Southwest Baking’s customers use a third-party audit system to guarantee accurate sizes of frozen goods coming from the plant, and want daily reports. “If we have a problem, we need to know in real time. The plant can produce about 11,000 lbs. an hour, so production can’t be off for three hours,” Wroblewski says. “The auditor doesn’t want data that’s a week old. At that point, it’s too late to make any changes.”
Under the Food Safety Modernization Act (FSMA), manufacturers are on their toes. “Food and beverage companies are well aware that you need access to all production data,” says Bob Trask, senior systems architect at Beckhoff Automation. “With OPC UA, historical options can be activated after a network connection is down and data will not be lost.”
The monitoring platform at Southwest Baking also provides trending and graphs for up to seven days and they also run a Rockwell Automation data historian for continuous data over longer periods of time.
Other OPC UA applications include connecting to computerized maintenance management systems (CMMS) to enable predictive maintenance practices and reduce labor and equipment costs. “For maintenance departments, OPC is a data gathering efficiency tool at its heart,” says Paul Lachance, president and CTO of Smartware Group.
From an OPC approach, maintenance departments are now connecting to CMMS platforms and OPC servers and clients to enable automated responses when equipment values move out of ranges, such as thresholds or time-based values.
“If an operating temperature strays outside of a set value due to a spike, that will trigger a corrective maintenance action, as opposed to a preventive maintenance action,” Lachance says. “Before a work order was generated due to the calendar (preventive); now one is created automatically due to operating conditions.”
These OPC UA applications demonstrate how this communication standard is redefining control options and production data visualization in the factory.
