ABB introduces wireless energy harvesting temperature transmitter

ABB has developed a standalone, self-powered temperature transmitter with WirelessHART, offering a cost effective and maintenance-free alternative to wired or battery-powered devices. 

Wireless instruments offer the ideal solution wherever it may be costly or impractical to run cabling. Battery-powered WirelessHART technology allows for quick and simple instrument installation to allow operators to monitor new process information to improve plant visibility.

However, the battery will eventually need replacing, incurring time and cost. Battery life can be prolonged but only by slowing down the data transfer rate, affecting the instrument’s response time.

These challenges are overcome by ABB’s self-powered temperature transmitter. Featuring a built-in thermoelectric generator (TEG), the device uses the Seebeck Effect to harvest electrical energy from thermal energy. The temperature difference between the ambient and the pipe temperature produces a voltage difference, which is then used to power the device. This technology enables the transmitter to be fitted onto a steam or process pipe, with the latent heat being used to provide the power needed for operation.

To help protect against the risk of a power failure, for example if the process medium or steam flow is deactivated or the temperature gradient falls below the 30K needed to power the device, the device also includes a back-up battery. Under ordinary circumstances, this battery should hardly ever need to be used, giving it a potential operating life of up to 20 years.

The status of the device can be relayed via WirelessHART to a centralised control system, including ABB’s System 800xa, which offers the necessary functions and tools to integrate wireless devices into the control network.

To help operators find out whether their application could benefit from using the self-powered transmitter, ABB’s service experts can perform a site survey. Using the results of the survey, they will advise on the suitability of wireless technology for the application, together with any steps that need to be taken to optimise its effectiveness.