Arizona Utility Co-op Insists on a Single HMI

Arizona Electric Power Cooperative (AEPCO) is a rural generation and transmission cooperative located in southeastern Arizona. Its SCADA system was designed one upgrade at a time over many years with a "run anything from anywhere mindset." That global access to information is helping AEPCO and its small staff of engineers, operators and maintenance technicians ensure continuous system uptime. And its instance on a single human machine interface (HMI) is making that job easier.

AEPCO plant operations consist of 60 employees working 24/7. Approximately 40 maintenance technicians handle mechanical, instrumentation and other plant maintenance tasks. Engineering staff includes two results (performance) engineers, one mechanical engineer, one electrical engineer and one controls engineer. "When I started here in 1992, I was one of 12 electrical technicians. Now it's six," said John Franklin, who is CEMS/Logic Systems Administrator. His department's staff of three is responsible for the network infrastructure, servers and workstations, PLC/PAC/DCS programming, and maintenance and design. This also includes all associated applications such as emissions monitoring, as well as security, data archiving and disaster recovery.

AEPCO insists that all new systems and system upgrades integrate with its Proficy iFIX software from GE Intelligent Platforms, St. Louis. Keeping the human machine interface (HMI) platform the same no matter what allows simple changes to be made by in-house staff without interrupting the existing processes, said Franklin. "We want to keep our own HMI, and iFIX is the easiest way to hook to a variety of things. We haven't found anything that iFIX couldn't overcome," he said.

Bill Pezalla, Energy Industry Manager for GE Intelligent Platforms, said, "Sophisticated tools in iFIX make it easy for the smallest utilities using in-house resources to implement accurate and consistent SCADA without the need for IT specialists. Users can perform maintenance and troubleshooting with tools that are immediately intuitive to Microsoft Windows users." Embedded Microsoft VBA and hundreds of off-the-shelf drivers and OPC clients and servers, for example enable customization.

AEPCO users can drag and drop new devices to quickly update on-line diagrams. For the production of operator displays, users can drop a device into a picture, and iFIX automatically adds a tabular display of all related secondary points-with the appropriate operator dialogs for safe, consistent control.

"We collect every point in the plant, from rainfall to visitors on site," said Franklin. "Our goal is to give the operator and the engineer all the information possible to aid in plant performance and reliability."

Notification tools range from Web services to PC based kiosks to automatic notifications. For Web-based communications, AEPCO uses Microsoft's IIS hosting reporting services, real-time unit status with iFIX Web Server, and diagnostic tools such as iFIX Webspace and Proficy Real-time Information Portal.

The iFIX open architecture makes upgrading the applications easier, because "we can focus on getting the most out of our field hardware choices without fearing communication issues," said Franklin. "With environmental regulations always changing, we have to be able to add or remove components to our reporting systems. iFIX allows for this to happen with minimal impact to the operations staff."

PC-based kiosk access

PC-based kiosks are located in key satellite areas such as water treatment and gas turbines. A user slides in his or her access card and a touchscreen keyboard comes up. Users can get the same information at a kiosk that they can anywhere else in the plant, but user-based restrictions prevent unauthorized access.

Because iFIX easily enables multiple methods of secure access to important systems, AEPCO can do more with less. For example, "it used to take three operators to run a facility," said Franklin. "Now they can start or stop any facility from a kiosk."

Franklin's department has merged site security access control into the SCADA system as well, using tools such as Windows PKI implementations and smart cards for both user log-ins and physical access. When someone swipes their card at a door and is let in, the system posts a picture of the person and what door they came in. If an operator is at his workstation, he or she uses the card to log in. If the person forgets to log out, the computer automatically logs him out. This helps AEPCO comply with National Energy Regulatory Commission (NERC) standards.

"We've been doing this for five years," said Franklin. "It was our way to track who started what pump, and now it helps with compliance. We don't use electronic signatures, but this tells us what everyone is doing."

Franklin said insisting on a single HMI has allowed AEPCO to stay uniform in its approach to control and monitoring, and enabled the coop's two-level lockdown method for security and logging of all user events. "It also means we don't have to train on other HMI packages. This has kept the facility clear of any parasite or mini HMIs that tend to pop up with new projects," said Franklin.

The iFIX open architecture makes upgrading the applications easier, because "we can focus on getting the most out of our field hardware choices without fearing communication issues," said Franklin. "With environmental regulations always changing, we have to be able to add or remove components to our reporting systems. iFIX allows for this to happen with minimal impact to the operations staff."

Renee Robbins Bassett, [email protected], is Managing Editor of Automation World.

For more information related to utilities products and applications, see http://www.automationworld.com/Utilities-112.