Emerson Rosemount Pressure Indicator Gauge, with WirelessHART

Emerson Process Management has announced a new WirelessHART transmitter, which is a modern design of the ubiquitous pressure gauge. With a 4.5” gauge face indicator, this Rosemount branded unit has a 270 degree scale, to give easy visual indication, for operators to see on site when needed, of the process pressure. But this unit offers a lot more than a simple gauge, it uses a modern piezo-resistive pressure sensor capsule, replacing the Bourdon tubes and the mechanical parts, which were always subject to wear and vibration. Safety is also improved, because the sensor gives two layers of process isolation: the unit is capable of withstanding 150X overpressure.


Then the modern electronics processes the measurement, to transmit this data over WirelessHART, as a normal pressure transmitter would, so eliminating the need to visually inspect all gauges on operator rounds. In addition, the electronics drives the standard visual display on the gauge, which uses a conventional needle indication. There is also the option to press a button and illuminate the dial so an operator can read the gauge locally. The battery in the unit has a typical ten year life.

An industry first?

The press release from Emerson did suggest that this development introduced the industry’s first wireless pressure gauge. In fact the idea of using wireless to transmit pressure gauge readings remotely is not new, since it was back in 2009 when Honeywell Process Solutions launched a OneWireless gauge reader, working over their mesh wireless network, which later morphed into ISA100. Developed in co-operation with Cypress Envirosystems, the unit was quoted to non-intrusively attach to the outside of any existing dial gauge, enabling a simple upgrade of the existing plant equipment, without stopping the process. Obviously this approach did not improve the pressure isolation or improve the tolerance of the basic mechanical sensor to plant vibration induced damage, which is where the new Emerson approach scores.

(c) Nick Denbow, Processingtalk.info