Why remote telemetry units are the smart choice

Online Editor

Philippe Aretz reveals how RTUs can facilitate a cost-effective roll out of IIoT solutions

With major industry players predicting lower than expected oil prices for the foreseeable future, organisations need to look for ways in which they can maintain margins and deliver shareholder value. Key to achieving this is greater efficiency, which at a practical level means making sure assets in the field operate at optimum levels and with minimal downtime. There is also a need to constantly monitor the environmental impact of operations and, above all else, ensure the safety of staff and public.

Remote telemetry units (RTUs) help oil & gas operators overcome these challenges. They provide continuous monitoring of remote fixed assets, data logging (meaning critical data from the field is not missed and is available for analysis), through to managing complex, remote automation and control applications without the need for operators in the field.

Proven in the fields of operation, latest generation RTUs collect and act upon the new information demands that are necessary to optimise the efficient and profitability of oil & gas operators. This article looks at some of the factors to look for in ensuring that the RTU you specify deliver these benefits.

Benefits of real-time data from remote telemetry units

The most valuable tool in meeting these new digitisation requirements is ‘information’. And the most appropriate device to collect and process this information is the RTU. They are microprocessor-controlled electronic devices – effectively computers in the field that collect and transmit data. They interface objects in the physical world to supervisory control and data acquisition (SCADA) systems. RTUs have a long-proven track in the oil & gas sector, where they are deployed on a range of assets from remote wellheads, pipelines and offshore platforms, through to downstream and distribution. In these applications they collect, store and act upon data, regardless of the surrounding environment.

The move to digitisation means that, historically, sensors were used to collect information. However, as good as sensors are, they only offer a partial solution and ignore key problem areas with data collection and information management. RTUs are specifically designed to address these limitations – they go further by gathering data locally, analysing it, acting upon it, and then reporting the resulting information to the control centre.

In many cases, the remoteness of oil & gas assets means communications can be limited, irregular or simply unreliable. RTUs solve this by being able to store information until it is required. Each piece of information is plotted against a timeline, so that engineers can understand the state of an asset at a given point. That means being able to look back in time to spot anomalies or trends. In simple terms, RTUs ensure that there are no gaps in information, which supports the drive towards efficiency and reduced maintenance budgets.

The RTU is the device at the edge, sitting between the control room and the field instruments, which provides a low latency response to changing site conditions as well as performing data filtering. The RTU ensures that only key, critical information is passed via the narrow communications links, minimising data throughput but maximising information throughput.

The ability to provide accurate, real-time data enables management teams to make better, more informed decisions. In addition, because RTUs do everything locally, it means if communications break down, they continue to run – maintaining a historical log and reporting back later. In remote locations, communications will fail regularly, although RTUs can manage this. For instance, the data that the RTU collects can be used to support maintenance decisions, and to verify that environmental obligations are being adhered to.

An important feature with any RTU is resilience to the site environment. That is especially true as easily accessible oil & gas reserves become scarcer, meaning that assets are in remote geographical areas. These environments, because of their extremes of temperature, can present challenges for all technology and specifiers already expect RTUs that can operate at temperatures between -40°C and 70°C.

RTU systems should have built-in redundancy and resilience. This varies from simple CPU backup to full redundancy of power supply, CPU, and communication paths. High availability can also be achieved via redundant processors, redundant power supply and redundant communications modules. It means they can manage intensive and future SCADA and telemetry applications, whilst avoiding system failure. Processor modules support hot standby redundancy; switchover from the primary to the backup processor will occur upon failure of I/O module scan or communications failure on selected ports.

Another challenge in remote areas is power supply and that is why RTUs should incorporate intelligent management of power consumption as well as battery or solar power sources. Historically, industrial networks were isolated from IT networks however, now they are deeply interconnected and as such need to be robust against cyberattacks. As a result, RTUs need to incorporate a range of state-of-the-art cyber security measures such as: firewall SSL (Authentication & encryption), HTTP, FTPS & SFTP, SMTPS, X.509 Certificates, IEEE802.1x and open VPN. Auditing should be carried out regularly according to IEC 62443 4 2 and ISO 27019.

Using remote telemetry units to upgrade older assets

The Industrial Internet of Things (IIoT) has resulted in an explosion of available information and RTU platforms have been developed to securely harness, channel and use this data as part of a smart network.

That provides the ability to upgrade non-smart devices because they publish information about their operation in real time. By harnessing and distributing the wealth of data created by previously unconnected, non-automated processes and equipment – making an old asset a smart asset by fitting an RTU – companies can collect and analyse operational data from all areas of their business, which drives efficiencies and reduces costs.

It’s one of the reasons why Ovarro has built IIoT capabilities into its RTU products such as TBox LT2. These are an important part of the jigsaw because traditionally RTUs have always been ‘edge’ devices, capable of monitoring, marshalling and transferring data from the operational technology (OT) environment. That means RTUs are the perfect vehicle to marshal and collect all the additional data available through IIoT devices and securely transfer it to the information technology environment for analysis.

A summary of why remote telemetry units are the smart choice

There has been a considerable improvement in RTU processing power and memory recently, which means they run and store data in the most challenging of applications. This increased processing power is helping facilitate the IIoT. A considerable area of opportunity is the ability of IIoT to create smart assets, even those that are part way through their lifecycle.

Some of the specific challenges that RTUs can help address are monitoring of flow, pressure, process equipment, temperature, optimisation and secondary recovery, complete well site automation and pipelines/transmission systems. They are commonly used for compressor and pump station automation, cathodic protection monitoring systems, storage facilities, pressure monitoring and tank gauging.

Information gathered, analysed and interpreted from these areas provide operators with the tools to improve efficiency, safety and maintenance costs as well as reducing shutdowns or fines due to environmental and safety incidents.

Philippe Aretz is with Ovarro

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