PLANT MANAGEMENT
SUITABLE SCADA SELECTION
On-premises or cloud-based SCADA? Cyril Pinede explains how to make the right choice for your facility
I
ntelligent sensors and automation equipment generate vast amounts of valuable operations data. If it is not managed correctly, this ‘big data’ can
be overwhelming. Te challenge is to present clear, actionable information to the right people at the right time, thereby improving their decision-making and helping to protect people, facilities and the environment. Helping to meet this challenge are modern supervisory control and data acquisition (SCADA) systems. Tere are two main types of SCADA systems; on-premises and cloud-based, although some organisations choose to use both layered together. Before investing in either it is important to understand the differences and benefits of each.
ON-PREMISES SCADA SYSTEM SCADA systems were initially developed in the early 1970s to be a universal means of remote access to a variety of local control modules, which could be from different manufacturers and allowing access through standard automation protocols. Back then, SCADA still had a control system architecture comprised of computers, networked data communications, and graphical user interfaces used for high-level supervision of machines and processes. Large SCADA systems have become
very similar to distributed control systems in terms of their function, while providing multiple means of interfacing with a manufacturing plant or locally housed assets. SCADA systems are used widely in the upstream oil and gas sector, but also
14
www.engineerlive.com
within other industrial applications, such as utilities, mining and many others. Te technology has evolved and now includes a wide range of features aimed at improving efficiencies, increasing safety, and enabling better operational and business decisions. Te first generation of SCADA systems
were independent, proprietary systems, with another mainframe acting as the back-up for connection to the remote terminal sites in case of failure. Advancements came through transforming the information and command processing from a central unit to a distributed network, where each station was responsible for a particular task. Tis improved resiliency and safety. However, there were no considerations given to security, long-term costs to maintain, or standardisation at that point. Subsequent iterations of SCADA systems focused on improving these aspects, using a ‘networked’ systems approach. Tis allowed SCADA to be spread across more than one local area network and separated geographically using a process control network (PCN).
CLOUD-BASED SCADA Today, the latest generation of SCADA is web or cloud-based, as opposed to the historical on-premises systems. Te growth of the internet and industrial connectivity has led to implementing web-based technologies, allowing users to securely view data, exchange information, and control processes from anywhere in the world, at any time. Cloud-based systems use internet browsers as the graphical user interface for the operator’s HMI. Tis simplifies the site
installation, reduces operating costs, and enables users to access the system from any device that is internet-connected, including mobile phones and tablets. Te biggest difference between on-
premises versus cloud-based is where the software and data are located, and who is typically responsible for the security, performance, maintenance and control. On-premises SCADA houses the software and data at the plant or asset site, and the entire scope of the hardware, software and architecture is owned and managed by the operator. Cloud-based SCADA, on the other hand, runs off web-based applications, where its management, including updates and security, is generally handled by the SCADA provider, who also takes on ownership and operation of the hardware, servers and software. It is important to note that even though cloud-based SCADA was developed after the on-premises type, both have their own advantages and disadvantages, and selection should be based on the application, scope and business strategy. It comes down to the level of control and ownership that is required, and where the assets are located.
MAINTAINING CONTROL OF YOUR OWN SOLUTION For businesses that are keen to manage their own SCADA, an on-premises solution is likely to be very attractive. By owning the devices running the software and storing data, and having them physically within reach, a business can decide and act on their maintenance, security, upgrades and
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52
