Viewpoint: pervasive sensing

To ensure operational excellence, industrial processes need better predictive capabilities that can quickly trigger responses.

It’s predicted there will be fewer process experts available in the future, so it’s vital to consider how to get the best out of the expertise on-hand.

This means ensuring experts aren’t spending most of their time travelling to a site, but are instead able to apply their knowledge remotely for plant diagnostics.

Today’s innovative sensor technology, including wireless and non-invasive sensors, has made installation cost-effective and maintenance straightforward. The embedded technology inside today’s sensors now allows them to provide direct actionable information.

Pervasive sensors

At the Emerson Exchange user meeting in 2013, the concept of ‘pervasive sensing’ was introduced to industry to explain how smart sensors gather actionable information to improve operations and maintenance.

A pervasive sensor is a robust sensor with no requirement for maintenance or calibration once installed.

It is typically a clamp-on sensor or externally mounted. Pervasive sensing devices include vibration sensing of rotating equipment, ultrasonic leak detectors, wireless steam trap monitors, corrosion and erosion detection technology, as well as wireless bolt-on surface temperature probes.

Using multiple sensors to gather information makes it possible to detect and respond to hazards before they become a danger to people and equipment.

The technology can also predict failures, reduce downtime, avoid environmental issues and identify potential security threats.

A pervasive sensor is a robust sensor with no requirement for maintenance or calibration once installed

In manufacturing, pervasive sensing helps in both process-critical and business-critical applications. Process-critical refers to process control and process safety applications. This data requires immediate response to prevent off-spec product or even plant shutdown.

Most of the equipment involved is already automated, since sensors generally connect to an existing process control system.

Risk managed approach

Essentially, pervasive sensing provides a better understanding of the condition of assets and the process performance.

This allows for a more predictive, risk-managed approach to intervention, ensuring that the correct equipment or replacement parts are available when required.

The move to risk-based management together with the emerging need to focus on collection of mobile assets rather than a fixed site will drive the future demand for pervasive sensing.

Information overload

However, one drawback to bear in mind is the possibility of information overload, as most of the data gathered by pervasive sensors acts to keep plant operators informed, rather than close process loops. If design engineers do not apply design principles that the workforce can manage, there may be so many alerts and alarms that the operators cannot keep up with them.

Jonathan Wilkins is marketing director of obsolete components supplier European Automation.