4 Easy Improvements Unlocked by a PLC Upgrade
6 min read
Upgrading an obsolete programmable logic controller (PLC) is one of the smartest decisions that an industrialist can make. Rather than a simple PLC migration, which tries to keep everything the same and leaves the door open to problems down the road, a PLC upgrade and its corresponding new software expands functionality, improves efficiency, and simplifies maintenance.
Whether you’ve decided to go the upgrade route or you’re still on the fence, we want to show you four easy improvements that you can make right now. We selected these options because they require minimal downtime, they’re low-risk, and they’re relatively inexpensive.
These improvements demonstrate their own ROI. That’s why we recommend taking a measured approach, where we take one step at a time, realize an ROI, and then have the option to put that return into even more growth.
1) Replace Old Relays and Timers with PLC Logic
Electromechanical relays were some of the first building blocks of industrial automation as we know it today. These devices let us send signals from one circuit to another; for instance, we can protect sensitive electronics and personnel by safely switching on a high-voltage motor with a relay that’s running at a much lower voltage. We can also program relays to create automatic control loops.
There are a few problems, however, with these older relay systems. First, they’re inflexible. Making any changes often requires rewiring, adding new hardware like timers, and a large time commitment from a licensed electrician. Second, whenever a mechanical relay opens and closes, the contacts will arc slightly, eventually destroying the relay. Lastly, if something does break, the troubleshooting process is long and complicated.
That’s why our first recommendation is replacing your old relay systems with solid-state relays (SSRs) that run on PLC logic. These relays provide the same protective benefits as their predecessors, but, since we can control them with PLC code, we realize greater reliability, maintainability, and flexibility. For instance, if we introduce a new point of automation, upstream in our assembly line, we can simply change the relay timing by rewriting some code.
It’s also much easier for technicians to troubleshoot a PLC than an electromechanical relay. “Maintaining the system is always a concern,” writes Mike Garrick, product marketing manager at Phoenix Contact. “A PLC has better diagnostics, and when the problem is found, the failed I/O card can be replaced. Relays have no intelligence, so troubleshooting can become an issue depending on the complexity of the relay scheme.”
One of the best reasons to make this improvement is to eliminate islands of automation. These isolated processes often lead to data disruptions, poor communication, frequent breakdowns, and increased operational cost. Since PLCs facilitate interconnectivity, this transition lets us centrally optimize operations, easily share data, and even save space on the plant floor.
2) Integrate a Collaborative Robot for Repetitive Tasks
One tried and true way to see an immediate ROI from industrial automation is by integrating a robot to handle repetitive tasks. That’s why our second recommendation is using the upgraded PLC to control a collaborative robot.
The Robotic Industries Association defines collaborative robots, or cobots, as “a form of robotic automation built to work safely alongside human works in a shared, collaborative workspace. In most applications, a collaborative robot is responsible for repetitive, menial tasks while a human worker completes more complex and thought-intensive tasks. The accuracy, uptime, and repeatability of collaborative robots is designed to complement the intelligence and problem-solving skills of a human worker.”
In fact, human robot collaboration can increase the efficiency of various industrial operations by 30-40%. We achieve these results by automating a wide variety of tasks, including packaging, palletizing, picking and placing, CNC machine tending, and much more.
For example, in the food and beverage industry, we may have a person standing at the end of the line, picking up bottles, putting them into a case, and taping it shut. We can easily program a cobot to take over this repetitive job. And, on top of that, by controlling it with a PLC, we can alter its functionality based on what we need it to do.
So, if we have a second type of bottle coming down the line that requires a different packing process, we can use the PLC to switch the cobot’s logic to match the new task.
3) Add Sensors to Ensure Product Quality
Quality assurance (QA) is a key step in manufacturing and other industrial processes because poor quality products result in production inefficiencies, wasted materials, expensive recalls, re-work costs, and even dissatisfied customers who demand returns. At the same time, QA is a time-consuming and expensive process, especially when an operator has to review each and every product.
When we put this all together, it’s not hard to see how automating this process with an upgraded PLC is advantageous. One of the simplest ways to go about it is by installing a camera, such as those from Keyence or Cognex. These solutions can perform various types of inspection, such as checking that a bag isn’t ripped, that a cap is properly affixed, or that the product has the right type of label on it.
Cameras are just one of many sensor options. Other types can determine properties such as distance, position, and proximity, as well as other intrinsic qualities like temperature and color. In this way, sensors can provide automatic QA checks throughout the manufacturing process.
4) Add Data Storage and Visualization to Reduce Mistake-Prone Paper Records
The last simple improvement that we can easily implement during a PLC upgrade is data storage and visualization. This can be as simple as asking the computer to automatically generate a timestamp when we start a batch, rather than having an operator write it down. Not only does this improve consistency, but it also gives us an audit trail we can use for compliance or later development programs.
A popular option is the Ignition SQL Bridge, which enables us to integrate PLCs and SQL databases in a variety of ways. This so-called 'Swiss Army Knife' can “move data bidirectionally, log huge amounts of data easily, synchronize PLCs with databases, create powerful recipe and batching systems, sequence entire processes, and more—your imagination is the limit.”
Of course, if you don’t want to use an open source option like MySQL, MariaDB, or proprietary options such as those found in the AWS Cloud—Redshift, DynamoDB, and Aurora, for example—then we can install a Standard Historian for built-in data collection and storage. Since there are so many customizable options, we’re guaranteed to find something that will integrate with your current systems.
Once we have this data pipeline in place, we unlock many other possibilities. We can integrate with human machine interfaces (HMIs) to give operators easier access to real-time information. This improves our ability to monitor machinery and reduces errors. Collecting all this data also gives us the chance to run analytics and find other areas for improvement.
Conclusion
Making the decision to upgrade an outdated PLC doesn’t mean we have to throw everything away and start over. Many automation companies will try to pressure you into a wholesale, immediate adoption of several emerging technologies, but we understand that that’s simply not how business works.
Outlier takes a different approach that’s defined by moderation. We believe that gradually improving your existing workflows leads to better outcomes, reduces risk, and lets you prove an initiative’s ROI before moving on to the next one. If you’re ready to take the next step in industrial automation, contact us today.