Sustainable SCADA: five practical steps for long-term improvement

Water utilities face many challenges, from pressures to adopt new technologies with dwindling resources, to aging infrastructure and outdated technologies. To succeed in this environment, a utility’s approach to its supervisory control and data acquisition (SCADA) system is critical.

According to Kent Melville, commercial engineering manager at Inductive automation. However, requirements inevitably change and utilities often look for short-term, cost-effective solutions. This can lead to random additional technology and hardware from multiple vendors, often with costly long-term consequences.

“What could have been a very fast and consistent system at the start, in the end is so complicated with all this different hardware that it’s impossible to maintain,” Melville said. The utility should then override the SCADA system and the process begins again.

Instead of using a fall-back approach with short-term solutions in between, Melville recommends a sustainable architecture that allows SCADA systems to adapt and grow over time. With the five incremental steps below, utilities can save time and money while improving availability and reliability.

Kent Melville, Director of Sales Engineering at Inductive Automation.

Step 1: Collect data from remote sites more efficiently

The first step towards a more sustainable SCADA system is to define a standard protocol for PLCs. By choosing equipment that supports a certain protocol, everything can use the same protocol and software can be exchanged more easily. To provide flexibility, Melville recommends an open protocol like OPC, MQTT, or Modbus, rather than a proprietary protocol.

In addition to choosing a new standard protocol, address issues such as bandwidth, latency, and connection that may impact data collection from remote sites. Melville strongly recommends installing edge devices at remote sites to poll locally and report by exception. This way, data is not lost when the network goes down, as it can buffer locally queried data.

Step 2: Save time and money with a server-centric architecture

A sustainable SCADA system should have a server-centric architecture, Melville said. Rather than maintaining many installations on many machines, a server-centric system only requires software to be installed on a centralized server. Since all data collection and visualization goes through this server, it is a single point of failure. Redundancy is therefore essential to maintain availability in the event of server failure.

A great feature of server-centric architecture is the licensing possibilities they offer, with the system being licensed by the server and unlimited for everything else. There are currently several options for SCADA systems that are licensed by the server. Melville recommends that you speak with your SCADA supplier to obtain a system that will meet specific sizing needs.

Step 3: Avoid upgrade headaches with cross-platform SCADA

Traditional SCADA systems tied to specific operating systems can pose problems for utilities when those versions reach their end of life and require organizations to perform costly upgrades.

To avoid this problem, Melville recommends using a fully cross-platform SCADA system. The system can then run on Linux, Mac or any version of Windows. “In a sustainable SCADA architecture, both the operating system and the SCADA should be independently upgradeable,” Melville said.

To achieve this, Melville said, take advantage of new versions of .NET, Java or other programming languages ​​that are cross-platform from the start. “Then they run in a virtualized environment on the computer rather than running directly on iOS,” he said. “With every version of iOS that comes out, they already do tests on their end to make sure the virtualized environment is still consistent and compatible with the programming language used behind the scenes. Since it runs on the virtualized environment rather than the actual OLS, you now have more flexibility, so things don’t break as much.

Step 4: Get more data with IIoT

The Industrial Internet of Things (IIoT) is about how you get your data. Obtaining large amounts of data from remote sites connected by radio, satellite, or cellular requires a lightweight protocol. This is where MQTT comes in, Melville said.

Using peripheral devices, the system can publish data with MQTT, an ultra-lightweight protocol that has only a two-byte overhead. MQTT is very secure and uses a pub/sub protocol that publishes by exception. It also uses the Sparkplug specification for storing and forwarding and automatic tag discovery.

Centrally, it requires an MQTT broker, where data is published and then business applications (including SCADA) can subscribe to it. The result is really powerful, Melville said, because you can decouple your data backbone from your applications.

“If your SCADA system is replaced, replaced, or any other application is replaced, you haven’t broken your chain of that data backbone because you’ve once again decoupled your infrastructure from your applications,” Melville said. .

Step 5: Maintain your system with alarm and report tools

A sustainable SCADA approach requires a quick response when something goes wrong. The best notification is a text message or a phone call, as staff can be informed immediately if they are on site or at home. Melville also recommends an alarm pipeline that elevates notifications if alarms aren’t responded to within a specific time frame.

Reporting efficiency is also an important key. Many organizations still rely on manual data reporting, which can be plagued by human error, Melville said.

Automatic reports reduce errors and allow you to receive reports immediately, saving you time. Organizations can still perform manual checks to ensure machines are collecting data correctly. However, if an organization chooses this route, Melville recommends that staff use a tablet where they can enter data directly into the system instead of writing information down and transferring it to reduce the number of steps in the process.

Michael J. Chiaramonte