How to Connect a Digital, Data-Driven Smart Factory
The reality is that most facilities are brownfield sites with legacy equipment. Here are the things you can do to get everything successfully connected.
The Industrial Internet Consortium describes a smart factory as the ability to “aggregate, analyze and act on data.” Aggregate, analyze and act are not, unfortunately, as distinct or delineated as they might seem. Aggregating data at the factory floor typically includes some analyzing and displaying, and that results in some acting by the end user. But there is still plenty to be done at the enterprise and cloud level for analyzing and acting. This blog focuses on aggregating on the factory floor.
In a perfect world, an industrial facility is a new, greenfield plant built with the sensors, controllers, networks and computers required to meet the end user’s desires for information. In the real world, an old, brownfield plant is the norm. There are machines, cells of machines and processes that are not connected to anything—they are islands of production with little connectedness. Clipboards might still be used to collect data.
The proverbial “elephant in the room” that gets ignored, while vendors extol the features of their hardware and software, is the old, legacy hardware and software in those brownfield plants. Aggregating data isn’t glamorous like colorful dashboards. Data is akin to the invisible studded wall that supports a glamorous facade. News flash! Just as facades aren’t possible without studded walls, dashboards aren’t possible without data.
The problem? Extracting data from old control systems. Here are some likely scenarios:
- No networks or point-to-point networks: Some old controllers have only a programming port—no network capability. Others have a port for a network to a human-machine interface (HMI), but it can’t be added to.
- All ports on the processor are occupied: Ports go to HMIs, I/O racks or a PC. None are open for new use.
- Obsolete and unsupported computers, operating systems and software: 486 computers, Microsoft operating systems such as Windows 95, 98, NT, 2000, XP, Vista, 7, 8 or 10. Most executable files for old operating systems won’t run on modern-day computers. VMware might work, but it’s a Band-Aid. Replacement HMIs from automation suppliers are no longer available.
So, what is the solution for hardware? There are multiple choices:
- Add sensors, either wired or wireless, with no modifications to the current control system. Examples are photo eyes, temperature, pressure, level, torque, vibration and speed. Connect them to a data concentrator or edge device. The downside of just adding sensors is that if there is important data in the machine control system, that data won’t be available. An example is the result of a calculation in a process control application.
- Tap into existing sensors by paralleling connections. Splitters can be used for current (4-20 mA) and voltage (0-10 VDC) signals.
- Tap into an existing network, which is possible only if the network is capable of an additional node.
- Use an open port on the processor. With luck, one is available. If necessary, use a bridge device to convert to Ethernet.
- Add or upgrade processors. Adding a processor (PC or PLC) for data aggregation while keeping the current processor for machine control won’t solve the problem of replacement processors being increasingly difficult to get, but that’s a topic of discussion for another day! Modernizing processors or controllers provides the best result, but careful installation planning is required to minimize downtime. New processors are network-ready, which lends them nicely to data aggregation.
- New or expanded networks as a hardware solution can be accomplished as follows:
- Leverage business networks through managed switches and secure VLANs.
- Install separate wired manufacturing network infrastructure.
- Install wireless devices to bridge gaps where wired networking is costly or infeasible.
- Wireless systems: point-to-point, mesh network.
- Cloud services, either internal and/or external can be added. A typical internal solution is an edge computing device.
- Live monitoring/analysis/historian can be accomplished by implementing hardware and software locally on the factory floor to store, compute and view data. Local devices also serve as a buffer and pre-analysis for enterprise software and Big Data in the cloud.
What is the solution for legacy software? There are multiple options here, as well:
- Use a virtual machine to execute the code.
- Replace scripted code (e.g., Visual Basic, C++) with commercial software.
- Modernize! There are lots of commercial packages to function locally on the factory floor to monitor/analyze/store (historian). Data from these systems are then sent to the enterprise for more in-depth analysis and display.
Incremental modernization to aggregate data can be implemented in phases. Everything doesn’t have to be done at once. And system integrators know how to do this!
A significant benefit of all the above steps to aggregate data is the process improvements that can be achieved when operators, managers and executives have information they’ve never had before.
Robert Lowe is co-founder and CEO of Loman Control Systems Inc., a certified member of the Control System Integrators Association (CSIA). Please see Loman’s profile on CSIA’s Industrial Automation Exchange.