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Rapid response to improve business performance

Rapid response to improve business performance

Here, we ask Matthew Hawkridge, chief technology officer at Ovarro, about remote telemetry units and why they can help improve business performance.

Rapid response to events and effective decision making are essential for maintaining a profitable organisation and efficient deployment of resources such as people and energy. One of the best ways of delivering this utopia is to gather information from industrial assets; RTU’s or Remote Telemetry Units, with their small size, multiple types of I/O, different communications modules and programming of processes capabilities as well as low power consumption make them the perfect platform for achieving this.

RTU deliver important benefits including early detection of problems, or continual automated interventions in order that assets operate within agreed parameters. In simple terms, RTU’s in an industrial setting allow instant access to the most relevant information needed to make data-informed decisions. Although RTUs were traditionally used to monitor and control remote field devices, they are now routinely specified for industrial processes as businesses gain a better understanding of their benefits. In these applications, the RTU connects to a plant control room or SCADA, providing a low latency response to changing process conditions as well as performing data filtering. They ensure that only key, critical information is passed securely via the narrow communications links, minimising data throughput but maximising useful information received.

RTU’s are widely used in the industrial sector for process automation and control as part of a supervisory control and data acquisition (SCADA) system. Effectively, RTU’s are mini-computers that collect data locally, act upon it immediately, and report securely to the central control room, whilst maintaining a local historical store as an additional backup.

RTU’s collect these additional data points from a vast range of individual pieces of equipment. For instance, new data points may replace manual dips tests to verify the accuracy of primary level sensors, track product density to ensure that the right product is in the right vessel or monitor product temperatures, inert gas blanket supply and pump vibration. There are benefits for engineers overseeing remote sites that are vulnerable to theft and vandalism, too. The opportunity list is virtually endless.


Key differences

The main difference between an RTU and PLC is that the former is highly suitable for assets spread over wide geographic areas because they use wireless communication. PLCs can be better suited to local controls, although there is now much overlap in functionality between the two and cost effectiveness of latest RTU’s mean they are often used for ‘near’ location assets.

RTUs, the field part of a SCADA system, are used to translate the physical world into digital and then send this data for storing, trending, analyse and action. Sensors are simpler devices, which means they are not designed to interpret protocol communication on their own like RTUs. That’s why RTU’s play a crucial role in digitising the inputs from sensors into protocol format and transmitting them to SCADA. The SCADA then issues control commands back to the RTU which in turn transmits electrical signals to control relays.

The single biggest advantage of an RTU compared to a PLC is that the environmental robustness of the former makes it the stand-out choice for demanding industrial and manufacturing applications.

RTU’s can be used in locations with extreme climatic temperatures and/or remote locations that are off the power grid. For instance, Kingfisher RTU’s have been selected as high availability process controllers with extensive communications capabilities for sites with temperatures ranging from -40C to +85C. 

Their resilient and secure nature, combined with independent communications links, redundant power supplies and redundant process controllers make them an extremely robust solution in these applications.

Again, RTUs can perform autonomous control in real time and then report to SCADA that it has everything under control. Engineers at the SCADA interface can ‘supervise’ the operations by setting new KPIs (Set Points) or updating instructions (open/close this, start/stop that, for example) for RTUs to then act upon and manage locally.


Can RTUs facilitate IIoT?

There has been a significant improvement in RTU processing power and memory recently, which is helping facilitate Industrial Internet of Things (IIoT). A significant area of opportunity is the ability of IIoT to create smart assets, even those that are part way through their lifecycle. For example, deploying RTU’s with latest processing power on an old asset can turn it into ‘smart’ asset. This helps engineers to make the most of their aging equipment and reduce lifecycle costs.

Let’s consider a real world case study.  Australian railway companies provide transport solutions for mine sites in remote regions, passing through some of Australia’s harshest environments. Maintaining free flowing transportation relies on monitoring and control equipment that is resilient and highly available. Any delay of a train loaded with valuable ore represents a million dollar per day hit to a mine site’s profitability. Operators also need to ensure the safety of staff, the public and the environment.

At key points in the railway network, specialised signalling equipment provides local management of railway line safety. Kingfisher RTU’s are utilised for the remote management and co-ordination of these single purpose safety devices. Each RTU maintains a timestamped log of every command sent to a signalling unit from the control room, the digital outputs from the signalling units to field equipment and the changes in status of field equipment. The logging of every event ensures that no historical data is lost, even if there is a breakdown in site communications. In addition, if an audit or post incident review is ever conducted, the log provides the information required to reconstruct the site status at a particular point in time.

Multiple devices work together in unison in railway control. In addition to signalling equipment, there are UPS systems, station lighting, arrival information systems and switchgear. Operators need to be able to monitor and control each and every device. The RTU provides a single, reliable interface to these systems as well as supporting numerous data protocols to gather data from and send commands to the myriad of devices used in railway control.

The RTU is a “Black Box” for the railway system, continually verifying and recording site operations. They are resilient to the environment, operate 24/7, report upon and log all key events and manage all site communications. They are the device of choice for remote monitoring and control of railway operations.


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