Wireless radar level transmitter complies with API 18.2 custody transfer standard

The transmitter – part of Emerson’s Plantweb digital ecosystem portfolio of transformational technologies, software and services – delivers accuracy which can be verified without having to open a tank’s thief hatch, thereby increasing safety.

 

“The API 18.2 standard places strict accuracy demands on level measurement instrumentation because high levels of uncertainty during custody transfer can have significant financial implications,” said Christoffer Widahl, product management lead with Emerson’s measurement and analytical business. “Measurement precision is therefore essential in these applications, and the Rosemount 3308 delivers the high accuracy required to reduce uncertainty and comply with API 18.2.”

 

An upgraded microwave module has made the transmitter more tolerant to difficult process conditions and therefore able to deliver a more sensitive and repeatable measurement and higher accuracy. API 18.2 requires level transmitters to operate with 3mm resolution and 4.7mm measurement accuracy, which is achieved when set up in high-performance mode. This then enables it to achieve the installed accuracy of 6.3mm required to comply with API 18.2. In standard mode, the accuracy of the device has been improved to 5mm.

 

Accuracy can be quickly verified using the Rosemount VeriCase mobile verification tool. This procedure does not require a tank’s thief hatch to be opened or any product to be transferred. Opening the thief hatch can cause high concentrations of hydrocarbon gases and vapours to be released, putting worker health at risk, eliminating this requirement is an important safety improvement.

 

In addition to providing the accuracy required for custody transfer applications, the Rosemount 3308 is also said to offer reliability in continuous level and interface monitoring applications in refineries, oil fields, offshore platforms and chemical plants.

 

Wireless technology significantly reduces installation and configuration time for level measurement applications and can typically reduce costs by at least 30% compared with a wired solution. The Rosemount 3308 can be installed and operating in less than an hour – transmitting data via a wireless gateway to a control system or data historian. Status information and device diagnostics are easily accessible from the control room, reducing maintenance requirements and enhancing operator safety by eliminating unnecessary field trips.

 

For more information visit Emerson.com/Rosemount3308.