"Yesterday, you couldn't do PID wirelessly," says Randy Balentine, DeltaV product marketing manager at Emerson. "Today, that's no longer the case."
What makes this possible, Balentine explains, is a new control algorithm. "We knew WirelessHART devices and the way they do non-periodic updates, and we understood how we could accommodate that in the PID algorithm and function block," he says. "We've held a PID steady in some of its calculations and not made ill-advised moves in the algorithm without an update. The proof and the technology are here at the Exchange." Two sessions will give a hands-on demonstration of the new PID algorithm in action.
They'll explain how WirelessHART was used for pH and temperature control of a single-use, disposable bioreactor at Broadley James. The technology is available to address most control applications, with scan rates as fast as 1 sec, supported by devices, gateway and DeltaV, explains Blevins. The PID is designed to work with WirelessHART devices that support period and exception reporting. However, he notes, the impact of faster updates on battery life must be considered.
The workshop will address performance compared with a wired transmitter, demonstrate how to address lost communications, and will share test results.
An overview of the separations research program at the J.J. Pickle Research Campus at the University of Texas will be the focus of another workshop led by Blevins, along with Frank Seibert, technical manager of the separations research program at the University of Texas at Austin, and Mark Nixon, manager, future architecture, at Emerson.
They'll address the motivation for the installation of WirelessHART, changes in the DeltaV system configuration for control using WirelessHART measurements, features added to modules and displays to enable control performance using WirelessHART, use of process and WirelessHART transmitter simulation and the results using WirelessHART in steam flow and column pressure control.
"Stripper and Absorber Control Using WirelessHART Transmitters," workshop sessions are offered on Wednesday, Sept. 30, at 3:15 p.m. in Osceola 1 and again on Thursday, Oct. 1, at 11 a.m. in Naples 3. At Texas' Pickle Research Campus, carbon dioxide removal from stack gas is a focus project for which WirelessHART transmitters are being installed. To find out more about implementation of the technology, Balentine will give a product update on DeltaV Engineering Tools on Sept. 30 at 10 a.m. in Sun 2 and again on Oct. 1 at 3:15 p.m. in Sanibel 2.
"We're extending the value of the PlantWeb architecture to encompass variable-speed drives and soft starters, even more intelligent use of bus technology, and extending it from HART and fieldbus to DeviceNet and Profibus-DP." says Balentine. His presentation will detail planned improvements to the DeltaV engineering tools in the areas of intelligent field device diagnostics, HART implementation and PID control. Each new feature, along with the benefits to the user, will be described. The workshop also will allow users to provide feedback on engineering tools' functionality to the DeltaV product marketing organization.