SCADA (Supervisory Control and Data Acquisition) is the fundamental software solution for managing large processes in many industrial manufacturing and infrastructure vertical markets and has also become the foundational information platform for Industry 4.0 and digital transformation.
Traditionally, SCADA has played the role of operator interface to large, complex, and distributed systems. Today, SCADA software has become so modular and scalable that it has evolved into the default platform for monitoring all aspects of industrial automation to help organizations drive continuous improvement and process optimization. In fact, a SCADA system is pivotal to maximizing OT and IT strategies for information management and analytics.
Keep in mind though there are many choices to consider when choosing SCADA software, all delivering unique advantages and disadvantages, and the solution you choose will be one that you will most likely use for many years to come (10+ years at least). For those reasons and more, it is extremely important to understand the selection guidelines for choosing SCADA software.
Selection Guidelines for Choosing SCADA Software
Below is an extensive list of selection criteria, and this information is crucial to making an informed decision about your SCADA system:
- Vertical Market Specialization – Has a proven track record as a SCADA solution of choice in your market.
- Code vs No-Code Capability – Offers configurable vs. programmable application development.
- Scalability – Handles both today’s and tomorrow’s requirements.
- Alarm Management – Offers flexible alarming and supports alarm standards.
- Data Archiving – Contains features for data storage, compression, retrieval, and disk space management.
- User Interface – Delivers a consistent user experience for visualization across various devices and client types, including read-only, interactive, local, and remote.
- Tag Management – Contains options for tag management - Flat Tag Model vs S95 vs UNS (Unified Namespace).
- Data Analytics – Provides tools to develop and manage analytics across real-time and historical domains.
- Report Generation – Provides capability for automated time and event-based reporting.
- Notifications – Offers capacity for email, SMS, and other notification means.
- Rapid Development – Contains time-saving deployment tools to replicate similar functionality – clone and multiply.
- Application Documentation – Contains documentation tools for as-built reporting.
- Workflow Management – Provides tools for managing multi-step processes.
- Recipe Management – Has the ability to set operating parameters based on system requirements.
- IT/OT Integration – Provides tools to read/write, display, and interact with relational databases.
- Trend Analytics – Delivers user tools for history data retrieval and analysis.
- Standards Support – Supports various industry standards (OPC, MQTT, FDA 21 CFR Part 11, ISA95, ISA18.2, etc.).
- Performance Speed & Management – Offers high transaction speed and tools for performance management.
- Reliability – Delivers 24x7x365 solution reliability.
- System Health Monitoring – Provides tools for monitoring operational performance.
- Redundancy – Supports high availability requirements.
- Northbound Protocol Connectivity – Provides client support through one or more standards or proprietary APIs and protocols.
- Southbound Protocol Connectivity – Delivers the required protocol(s) robustly and reliably.
- Flexibility – Contains features and benefits that are differentiators at a detail level.
- Distribution – Is available locally or internationally.
- Interoperability – Plays well with other applications.
- Operating System Support – Is supported on the operating systems important to you.
- Ease of Use – Is designed for user or programmatic configuration.
- Technical Support – Offers quality technical support and various program support types.
- Proven – Should be widely used in the market.
- Vendor Endorsed – Delivers protocol owner endorsement of the solution.
- Certifications – Meets protocol certification requirements.
- Price – Available as a cost competitive solution, especially when considering total cost of ownership (TCO).
- License Model – Offers a license model that fits your OpEx/CapEx budget.
Vertical Market Specialization – As a software solution, SCADA gained popularity along with the introduction of personal computers in the 1970s. Today, there is a wide variety of SCADA software solutions to choose from, and SCADA has become commonplace in every industrial manufacturing and infrastructure vertical market.
Key markets that have driven specialization in SCADA software include oil and gas, pharmaceutical, food and beverage, automotive, chemicals, building, factory automation, water and wastewater, power and utilities, transportation, and general-purpose manufacturing of all kinds.
As you review SCADA software solutions, pay special attention to the unique functionality that may exist for your vertical market application. Key areas of focus will be the support of vertical market standards, device communications, and graphic symbol sets/analytics unique to your market.
Code vs No-Code Capability – Another SCADA aspect to consider is whether it offers programmable (code) vs configurable (no-code) application development because this capability will have a significant impact on both the commissioning cost (startup cost) and the total cost of ownership (long term management cost) of the solution.
Commissioning is often carried out with the expertise of a system integration company. Long-term management may also be handled by a system integrator but is often handled in-house or through a combination of the two. Many SCADA software solutions are oriented to a development environment that delivers support for many of the basic requirements of an application, leaving room for any additional requirements to be fulfilled through custom development by the system integration partner.
While custom software development for a code SCADA solution enables the ability to do virtually everything in automation, it does so at the cost of extra development time, the introduction of added complexity, and the need for additional troubleshooting/debugging with ongoing maintenance. A no-code SCADA solution may be equally flexible, especially if the vendor has a long history in the business with an established expertise. Configurable solutions are easier for end users to adopt and support long term.
System integrators often like code solutions as these types of SCADA give them a greater opportunity to customize and deliver a unique solution that they will most likely be involved with supporting long-term. In the mature market of SCADA, it is almost always better to select a proven and configurable no-code solution. However, all solutions, whether code or no-code, offer customization options for challenging applications.
Scalability – SCADA software is selected for the application at hand and may be enhanced over time, perhaps over dozens of years, to accept new data sources and manage new requirements. The SCADA software you select should deliver flexible licensing and quality support to assist with your long-term ownership.
You will want to review product release dates, feature enhancements, etc. to ensure the SCADA software vendor is actively investing in the solution, so the company will be able to address and keep addressing your needs in the coming years.
Also. it is important to consider that your application may grow from an architecture of one server node to a network of many nodes. Review the data architecture of the SCADA software to understand how data is accessed in a distributed environment and how easy it is to morph your architecture to distribute functions, as necessary. This may mean moving historization or reporting from a single server to another dedicated server for improved performance. Ultimately, the SCADA software you select should give you flexibility in these areas.
Alarm Management – All applications will benefit from alarm or event management. Some applications have greater demands on alarm management and may even require the support of alarm management standards such as ISA 18.2. Advanced features in alarming which include alarm shelving, alarm suppression, and alarm acknowledgements can become very complex.
Notification schemes should exist within your SCADA solution for you to select the proper users to notify or trigger workflows to manage alarm responses. Standards such as the OPC Foundation OPC UA A&C (Alarms and Conditions) are excellent in enabling compatibility with other software solutions in the market.
Data Archiving – Your SCADA of choice should include features for data storage, compression, retrieval, and disk space management. Data archiving, also known as data logging and the more sophisticated data historization, is an extremely important part of a serious SCADA software solution.
In smaller applications, data archiving may simply be accomplished by logging to files or to a relational database. In larger applications, performance will benefit from data compression techniques to minimize storage space and improve response times.
Many SCADA software solutions also offer data management tools to archive old data for memory management. Standards also play a significant role in data archiving. Ideally, archived data should be available for both IT and OT use. In the IT domain, relational database standards apply for data access.
In the OT space, standards such as the OPC Foundation OPC UA HDA (Historical Data Access) will play a vital role in the integration with other OT software solutions. Pay special attention to the OPC UA HDA aggregate functions as these are a major differentiator in how OT solutions can query for analytically reduced data sets.
User Interface – With the advancement of internet graphics, every SCADA delivers a user interface. Most SCADA graphics are both scalable across mobile and desktop interfaces and are also fully web enabled. There has been a long history of graphic technologies and now virtually all SCADA software has caught up.
Some are still supporting legacy programming environments such as VBA (visual basic for application) while others are built on more modern tools for their different configuration environments. Users may use one tool to create web-based graphics and another for desktop graphics.
Obviously, the requirement for scripting tools in user interface design are not optimal. The ideal solution will offer a complete point-and-click solution for all user interface development. Tools should exist for data display and animations, etc.
A SCADA should also offer special objects for trends, alarm displays, data entry, relational data display, as well as a complete array of standard objects to match your vertical market. Some solutions offer 3D graphics animation, a capability that is at the forefront of user interface technology, so keep an eye out for these.
Tag Management – Tags are the names for variables in your system. Data is typically requested by using the tag name. Modern SCADA solutions offer very robust tag names with hierarchical organization into sites, areas, lines, equipment, etc. This capability is also known as an ISA S95 definition. Other systems refer to this as asset-based information modeling. Unified Name Space (UNS) is another concept for creating a directory of all tags and meta data associated with them.
In addition to organizing access to data through information modelling definitions, it is equally important for a SCADA to have the capability to apply analytics to these models to perform rapid and less error prone development.
Moreover, graphic objects should consume modelled data, and analytics should apply to modelled data. This is an area of active technology development with organizations such as CESMII and the OPC Foundation that drive the adoption of information models to enable Industry 4.0, digital transformation, and smart manufacturing.
Data Analytics – Data analytics is supported by all SCADA software solutions these days. Differentiators in this area include SCADAs that use templates, models for analytics, rules-based analytics, and workflows applied to analytics as solution accelerators. These SCADAs can also combine real-time analytics with analytics on both relational database and historian database sources.
Report Generation – Report generation is often a requirement in SCADA applications. This is also an area of specialization, and few SCADA vendors offer high-quality reporting, typically deferring that capability to third-party technology providers.
A leading SCADA solution will offer good quality reporting with built-in tools, while also offering standards-based interfaces for third-party support, including relational database interface standards and OT standards such as OPC UA – DA (Data Access), HDA (History Data Access), A&C (Alarms and Conditions). OPC UA HDA aggregate functions are a key differentiator in accessing analytically reduced data sets for report generation.
Notifications – Notifications are a powerful way to ensure users respond to anomalies quickly and efficiently. A SCADA’s capability in this area can be a major differentiator.
Some solutions offer good internal capabilities while some rely on custom software development. Still there are others that rely on third-party solution providers. Again, consider the SCADA support for both IT and OT data standards, which will be valuable in accessing the information to support notifications.
Rapid Development – Most SCADA applications have a significant requirement for repetitive configuration tasks. The configuration work completed for one plant can apply to another plant, from one line to the next, and from one piece of equipment to another. Tools for the replication and automated modification of an application will greatly enhance the developer productivity and reduce the chance of errors.
These tools are often referred to as cloning or multiplication tools. Ideally, the SCADA software configuration will be stored in a standard format, perhaps a relational database. This capability greatly enhances the ability to rapidly deploy highly scalable applications.
Application Documentation – Generating application documentation is crucial for training/education and change management. The SCADA should be able to store its application configuration as a common format (files or relational database tables) and should contain documentation tools that translate application configurations into human readable forms.
Workflow Management – Most SCADA software solutions are designed for real-time operation – operator interfaces, alarm management, and analytics. Newer SCADA software solutions offer an additional focus on time-based or event-based decision trees and data integration from IT sources (relational data). Even more sophisticated SCADA software will manage workflows, take results from analytics or alarms, etc., and follow procedures for notification, distribution, etc.
Recipe Management – A recipe can mean different things to different users. We may think of recipes as packaged changes to go from manufacturing product A to manufacturing product B. But recipes can also be considered as a set of parameters to run in any particular state. For example, the alarm levels for operating at full load as opposed to operating at minimal load. A SCADA with recipe management can adjust conditions based on product or operational conditions, an essential manufacturing capability.
IT/OT Integration – SCADA software is bridging the IT and OT gap to deliver analytics across both domains. A top SCADA should offer high quality interfaces to be able to retrieve, analyze, and display data from relational database sources and traditional OT device sources.
The ability to integrate data from both the IT and OT domains is critical to accelerating a digital transformation. In addition, IT infrastructures are rich with security, performance, and reliability data, so the ability to tap into this information domain is critical to running the most reliable environment. The support for IT protocols such as SNMP should also be a standard feature of every SCADA software.
Trend Analytics – Data trending is one of the most powerful ways to understand your process, so a SCADA should provide user-friendly tools for historical data retrieval and analysis. The SCADA should offer tools for pre-defined trending as well as ad-hoc trending.
An advanced SCADA will also offer tools for highlighting data, adding comments, and exporting data for use in other analytic solutions. Collaborating on analyses and sharing results with others are also important, and modern trend tools can facilitate this.
Standards Support – Standards have never been more important. Today’s solutions are often integrations of best-in-class products. The support of industry standards ensures that products will share data efficiently and reliably. There are many standards in SCADA, both in technology and in support for vertical markets.
For technology, look for OPC Foundation support and OPC UA compliance. For vertical markets, look for 21 CFR Part 11 in FDA regulated markets. PackML is common in food and beverage applications. ISA 18.2 is common for alarm management in the process industries. There are also best practice guidelines around high performance operator graphics, delivering decluttered interfaces and progressive disclosure to improve operator performance. A modern SCADA will have support for all of these.
Performance Speed & Management – A top SCADA will have high transaction speed, display and analytics responsiveness, and performance management tools. The need to consider performance in a SCADA will vary greatly with the size and character of the application. Be aware of the application’s needs and be sure that your SCADA has health monitoring capability.
Reliability – A modern SCADA will deliver 24x7x365 reliability. Considerations need to apply to both fully functional operation and operation when some devices are offline. Consideration should also be given to communication line quality, for example error rates in wireless configurations. Quality device communications should adapt to these varying situations and recover automatically.
Redundancy – Investigate how a SCADA supports high availability requirements. SCADA often supports architectures for higher availability, and these may include redundant communications paths or complete SCADA server redundancy that is invisible to a client application. High availability may also rely on hardware platforms like those from Stratus or virtual machines.
Northbound Protocol Connectivity – A SCADA should provide client support through one or more standard or proprietary APIs. Most applications are becoming the integration of best-in-class software components. The support of communication standards will be critical to enabling this integration.
Look at the OPC versions that the SCADA supports. Options are OPC Classic versions of OPC DA, OPC A&E, OPC HDA and the newer OPC UA with support for data access (DA), alarms and conditions (A&C), and historical data access (HDA).
While OPC UA is a complete protocol with data structures and transport, there are newer forms of OPC UA based on the MQTT transport. Often, OPC servers will support a number of northbound APIs for use in different integration scenarios. Internet and IoT architectures benefit from publish/subscribe protocols such as MQTT and AMQP while SCADA architectures benefit from poll/response with reporting by exception. There are also proprietary protocols such as Suitelink and EDA (Easy Data Access) that support particular SCADA software solutions.
Southbound Protocol Connectivity – A SCADA should deliver robustness for your required protocol(s). Southbound connectivity offers communications, typically both read and write, to the devices in your automation system. The most common protocol in the industrial automation world is MODBUS, delivered back in 1979 as a serial protocol and now adapted over time to Ethernet.
In the IT domain, SNMP (Simple Network Management Protocol) is very common. In the power domain, there are protocols such as 61850 and DNP3. In oil and gas, many count on the reliable collection of electronic flow measurement (EFM) data as crucial to their operations. In building automation, there are BACnet and BACnet/SC.
Various markets and vendors have introduced protocols that are adapted to best support vertical markets and unique applications. The latest technology to consider is Ethernet with Time Series Networking (TSN) supported by an industry standard protocol called CC-Link IE TSN. Other industrial ethernet protocols include PROFINET, Ethernet/IP, and EtherCAT.
There are dozens of current day protocols and an equal number of legacy protocols that are supported by many different OPC server providers. Modern OPC servers will support more than one protocol at a time. These are often sold as individual drivers, bundles of protocols, or a complete suite.
Flexibility – At a detailed level, look at what features and benefits are differentiators in a SCADA. Flexibility in a SCADA can range greatly and becomes more important in larger or more demanding applications.
Flexibility may involve the support of non-standard architectures, runtime configuration, remote configuration, API-based configuration, the ability to import and export configurations, application documentation, and more. In small and simple applications, flexibility is not necessarily a differentiator, but in larger and more demanding applications, it can become a serious area of differentiation between SCADA software offerings.
Distribution – Be sure the SCADA is available locally or internationally. Check if the products are sold through distribution or direct and if the SCADA software solution is recommended or private-labeled by OEMs in the industry. These are factors to consider in comparing one offering to another in terms of market reputation. Bear in mind that most SCADAs allow you to download a trial for test purposes before purchase, so look for this.
Interoperability – A top SCADA plays well with other applications. The foundational requirement of a SCADA is typically to co-exist with other applications on one computer. This may require the tuning of priorities or the special allocation of computer resources. It may also require running different applications in virtual machines. You will want to make sure your SCADA of choice supports your system and IT security architectures.
Operating System Support – A SCADA should be supported on the operating systems important to you. In the world of industrial automation, the most common platform is Microsoft Windows. Linux is also becoming very popular and Docker equally so. You will want to make sure your OPC Server runs on both workstation and server configurations and in scenarios with virtual machines.
Ease of Use – A SCADA should be designed for user or programmatic configuration. The ease of configuration is also a major factor in the selection of a SCADA. Options for configuration include manual configuration through a set of configuration menus and selections; programmatic configuration through a set of APIs that enable the support of external tools to automatically generate a configuration; and application configurations that are often stored in easy to access file formats or databases. In many cases, tools for export and import are also available to support configuration and documentation in other software solutions, often Microsoft Excel.
Technical Support – A SCADA vendor should provide quality technical support and various support program types. Check if the SCADA provider is a long-term viable solution provider. Also check if there are regular releases of the SCADA software and if there are updates to the latest technology, the latest security patches, and enhanced functionality. It’s crucial to know this information before you choose your SCADA.
Proven – A SCADA should be widely used in the market. In today’s software world, most offerings have been developed for localization (international language support). Leading solutions will be sold globally and will have the support for operation in various languages. Your application may only need English support, but for multi-national corporations, companies that have proven themselves on the global stage are more likely to deliver long lasting reliable solutions.
Vendor Endorsed – A SCADA should deliver protocol owner endorsement. The selection of a SCADA becomes simple if the device vendor makes a SCADA recommendation for you because they have vetted the solution and know its operation along with the available products. For example, Mitsubishi Electric has long endorsed and subsequently acquired ICONICS, and ICONICS’ SCADA is the product of choice for use in Mitsubishi Electric applications.
Certifications – A SCADA should meet protocol certification requirements. There are several seals of approval that should be considered when reviewing SCADA. The OPC Foundation offers a product certification process and database that lists all products, both certified and not. There are also certifications for the various device protocols that are available.
For instance, BACnet and BACnet/SC are protocols that are commonly certified with a seal of approval from the BTL (BACnet Testing Laboratory). CC-Link is tested through the CLPA (CC-Link Partner Association). Check if the managing authority of the protocol you are using offers a certification process and that the OPC server of choice has met the certification requirements.
Price – A SCADA should be a cost–competitive solution. The price of SCADA software varies greatly and is a major area of competition among vendors. It is worth reviewing the market offerings to compare technical abilities AND pricing to ensure you make the right choice for your application. Also, be sure to consider your long term cost of ownership as this will be many times more than the initial cost of your SCADA software
License Model – A SCADA license model should fit your OpEx/CapEx budget. License models for SCADA are currently enhanced by most SCADA vendors to match the licensing models of the IT space – monthly or yearly expenses over one time license costs.
While perpetual license models with annual support programs were the norm just a few years ago, models now include annual subscription support to fit OpEx (Operational Expense) rather than CapEx (Capital Expense) plus annual support pricing scenarios.
Final Thoughts
In summary, selecting the right SCADA is a crucial decision that can significantly impact your manufacturing and infrastructure performance, reliability, and overall success of your IT and OT systems. Factors to consider include performance, reliability, redundancy, technical support, northbound and southbound protocol connectivity, flexibility, proven track record, distribution, compatibility, operating system support, pricing, licensing model, ease of use, vendor endorsement, and certifications.
By carefully evaluating these and other criteria and considering the specific needs of your application, you can make an informed decision and choose the SCADA that best meets your requirements.