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A Powerful Migration Option for PID Tuning
Now that Rockwell Automation no longer offers RSTune and RSLoop Optimizer, customers have a compelling option through the company's partner program.
The Rockwell Automation Encompass™ Product Partner program offers a dynamic solution for Proportional-Integral-Derivative (PID) loop control tuning software through its partner company Control Station, Inc. As of September 30, 2011, Rockwell Automation has discontinued the sale of RSTune® and RSLoop Optimizer™. The company will honor existing support contracts, and advises its customers to seek migration elsewhere.
Connecticut-based Control Station is the only member of the Rockwell Automation Encompass Partner Program recommended as a migration option.
PID loop control is essential so controllers can perform vital functions for manufacturers, enabling complex production processes to operate in a safe and profitable manner.
Control Station offers the LOOP-PRO™ TUNER (Allen-Bradley® Edition), an integrated PID diagnostic and optimization solution that analyzes and tunes controllers on the user's network. It's a unique version of the award-winning LOOP-PRO Product Suite that supports Logix-based programmable automation controller (PAC) and MicroLogix™ controller algorithms.
Open-Loop or Closed-Loop
The software is uniquely equipped to model oscillatory and noisy process data. That allows users to improve the performance of processes with challenging conditions such as long lead times and those that are being operated during start-up and cutover.
Whether controllers are running in open-loop or closed-loop, LOOP-PRO TUNER accesses real-time process data by using Rockwell Automation FactoryTalk® Gateway or RSLinx® software (OEM version or higher). It can be installed on a standard computer workstation or on a shared computer network, or it can be integrated with the user's human-machine interface (HMI) and launched via a command line to any PID control loop. LOOP-PRO also can tune PID controllers using historical process data.
Originally developed to support PID and PIDE, LOOP-PRO now supports other forms of the PID controller used by Rockwell Automation customers. In addition, the software supports Add-On Instructions (AOI) that have proven instrumental to the growing community of process OEMs. The latest release, version 1.6.0, supports the Rockwell Automation Internal Model Control (IMC) block structure and includes advanced statistics for more comprehensive performance analysis.
Multiple controllers can be tuned simultaneously using a single license of LOOP-PRO. That feature is especially crucial when tuning cascaded or other interacting PID loops.
Key Differentiator
Control Station pioneered the ability to tune oscillatory control loops without first settling the process. In 2008, the company filed its patent application for the Non-Steady State (NSS) Modeling Innovation™, a breakthrough capability for controller tuning and process optimization.
"LOOP-PRO's ability to model oscillatory and noisy data is a powerful differentiator within the category of PID tuning products," says Ben Mansfield, marketing manager for the Rockwell Automation PlantPAx™ process automation system.
"If customers no longer have to wait for their loops to settle out before tuning them, then they save valuable time. They can improve the performance of loops that were previously 'off limits' due to challenging dynamics. We've found no other product on the market with that capability, and it clearly bolsters our PlantPAx offering," Mansfield says.
The company's NSS Modeling Innovation eliminates the need for a steady-state condition when tuning PID controllers. Whereas other tuning products calculate model parameters using one or more initial data points as a "known," LOOP-PRO makes no such assumption. Individual data points aren't assumed to be either "known" or more important than others, so LOOP-PRO analyzes the entire range of process data. This effectively removes the requirement for a steady-state condition.
"If tuning software requires a steady-state to function properly, then you're usually better off flying by the seat of your pants to calculate tuning coefficient," says Jim Sybrandy, MPC engineer, Praxair, Inc. "It's LOOP-PRO's integration with our existing Rockwell assets and NSS technology that sets the product apart.
"We recently evaluated LOOP-PRO against a variety of tuning tools and used LOOP-PRO to tune several interactive PID loops that would go unstable when outside a narrow range of operation. The results were evident: LOOP-PRO handled these difficult loops and allowed us to quickly stabilize control and to implement our MPC strategy. Additionally, LOOP-PRO cut tuning time by 2/3, utilizing a repeatable and effective tuning method," Sybrandy explains.
Powerful Partnership
"Rockwell is moving fast, and they've set lofty goals in terms of new process capabilities," says Bob Rice, Control Station's Vice President of Engineering. "We've aligned our product roadmap to keep pace. The more we remain in synch, the tighter the integration and the stronger the value to end users."
"The technologies that Control Station brings are highly relevant to our solution strategy," notes Chris Vaidean, global account business leader at Rockwell Automation. "Just as important, they share the same commitment to collaboration and customer satisfaction as we do."
When asked to comment on Control Station and the Rockwell Automation collaboration, Bruce Macdougall of Authorized Allen-Bradley Distributor North Coast Electric says, "We've worked with other tuning software companies in the past, and it's been a chore to get support. With Control Station, it's different — someone either picks up immediately or gets back to me fast. They always seem to be there to help me, which allows me to better serve my customers. That's a partner."
Click here to download Control Station's free PID Tuning Guide."
Control Station, Inc.
www.rockwellautomation.com/go/p-controlstation
Rockwell Automation Encompass Product Partner Program
www.rockwellautomation.com/go/tjencompass