Technology Qualification of Wireless for Control

20120531-110858.jpgThe application discussed in this workshop was on wireless sensor networks on offshore oil & gas production platforms in the North Sea.

Advantages cited for the use of wireless technology include project cost savings, weight savings from the avoidance of cables and cabling infrastructure, installation time, incremental device additions over time, and greater measurement coverage. Challenges included battery maintenance over time, latency time synchronization, security, regularity, and reliability, data management and integration, multiple wireless standards, supplier interoperability, and greater competence. On security and reliability, the concern was more with what if scenarios such as intentional signal jamming. Actual operation has been robust.

This oil and gas company has qualified wireless instrumentation for monitoring applications. They are currently testing wireless devices in closed-loop PID control. For the wireless monitoring applications, tests were performed with two wireless pressure sensors placed in parallel with two wired pressure transmitters. Other wireless temperature sensors were added to try to create wireless traffic. Logging latency was very important to the test. They have worked through some issues in getting accurate timestamps end to end to get these latency figures. Other tests are being performed for vibration monitoring.

Some applications shared included monitoring of casing and tubing pressures on wellheads, heat exchanger pressure and temperature monitoring, and other skid pressure and temperature monitoring.

Feedback from the early installations include quick and easy installation, high reliability, no wireless interference, and the operators are satisfied. If operators are not happy with a technology used, it will not be successful.

This company is also doing testing on wireless sensors for safety functions. A challenge is that wireless gas detectors and wireless process measurements is that they share the same airspace which can be viewed as not meeting the separation requirements outline in the IEC 61511 safety standards. The discussions to resolve this are early on.

Posted Thursday, May 31st, 2012 under Emerson Exchange.

One comment so far

Leave a Reply