The two organizations also teamed up with system integrator Onyx Engineering Ltd. and consultant Insyght Systems to upgrade WUC's SCADA system, and help it implement wireless tablets for plant-wide control. To address the outdated controllers, Onyx installed nine Allen-Bradley ControlLogix programmable automation controllers (PACs)—eight with redundant powers supplies and one non-redundant. The SSB team helped design the control panels and supervised their installation. The PACs are integrated to help the utility's operators access plant-wide production information with real-time visibility of water quality, as well as trending loads, levels, clarity and alarms—ultimately enabling better plant management.
To improve WUC's data tracking, tracing and reporting capabilities, Onyx installed Rockwell's FactoryTalk VantagePoint software, which delivers unified access to virtually all plant
information sources (Figure 2). By tapping into data gathered by FactoryTalk Historian software, FactoryTalk VantagePoint provides visibility into historical production data by putting the information into context via web-based reports. These reports provide role-appropriate visualization of high-level desktop dashboards. Prompt reporting capabilities are helping WUC stay ahead of regulations, and allowing real-time changes to plant processes to avoid downtime, fines or worse.
To further improve operations, Onyx and Rockwell integrated more information software. For instance, FactoryTalk Asset Centre change-management software enhances security through a set of asset-centric tools, which document and record all changes made to production on a role- and password-based system. FactoryTalk View Supervisory Edition (SE) HMI software supports distributed-server application, allowing maximum control over plant information. And, all programming was standardized to ease troubleshooting and future expansion of the control system.
"We've also got an aging workforce," adds Stuart. "Within 10 years, we're likely to lose all of our operations guys and a lot of our institutional knowledge. Also, there was little or no redundancy on the software we had, so we would have been out of luck if there was a failure," adds Stuart. "So our operators customized the FactoryTalk View SE software to match the unique needs of our operations. Being able to capture our operators' knowledge in this new SCADA system was invaluable."
In addition, WUC replaced conduits and wires from each I/O with ControlNet networks to help reduce wiring and installation costs, increase reliability and enable point-to-point management and troubleshooting. ControlNet is also used to transmit electrical information, bus voltage, motor data and network security to operators using the Common Industrial Protocol (CIP).
Allen-Bradley Centerline low-voltage motor control centers (MCCs) provide the controllers with soft starting and stopping of the continuously run motors, and Allen-Bradley PowerFlex AC drives provide the variable-speed motors with energy savings on pump loads. Allen-Bradley IntelliCenter software connects the MCCs with the rest of the plant, providing real-time diagnostics and MCC documentation to help maximize MCC and related equipment performance. Medium-voltage soft starters were installed in the synchronous and non-synchronous motors, and medium-voltage PowerFlex AC drives replaced the step-up/step-down drives.
Besides providing the products necessary for a plantwide control system, Rockwell Automation also supported WUC with other services. Through comprehensive network validation, Rockwell's engineers verified the installation and operation of WUC's new network. This ensured that the system was consistent with current functional requirements and that WUC could hit the ground running after migrating to the new control system. They also provided onsite training to WUC's operators.
With a robust SCADA system in place, WUC was able to achieve its ultimate goal of moving to a platform uses wireless, tablet-based controls. Also, Stratix industrial Ethernet switches provide secure integration with the enterprise network, so employees can confidently use the wireless devices without fear of outsiders hacking the system. Operators are now free to make rounds and take samples anywhere in the plant without the risk of missing an alarm because they were not within earshot of the control room.
Smarter SCADA Means Safer Water
The new SCADA system at WUC was commissioned in early 2010, and completed under its $3.8 million budget in January 2011. WUC became the first water provider in Ontario to use wireless tablets for plant control, and in August 2011, the plant transitioned from two operators per shift to one. The new system also eliminated the risk of single-source failure, and has helped reduce the risk of reporting errors by automatically tracking and tracing plant data.
Improved real-time control helps reduce downtime since operators can now proactively fix problems. When an issue does occur, the tablet allows operators to work directly with maintenance professionals at the source of the problem, rather than communicating commands over a phone or radio from the control room.
In the future, WUC plans to integrate its laboratory information management system onto the FactoryTalk VantagePoint software, and also use the new control system's power monitoring capability to check separate electrical feeds, determine how much power is used for pumping at different flow rates, and improve pumping efficiency. The ability to determine the most efficient flow rate will give plant management and staff the ability to optimize the backwash and chemical process dosing by 2013.