This project consisted of replacing programmable logic controllers (PLCs) in 12 control panels distributed around the plant and in 13 remote facilities that communicated with Iowa City’s Water Treatment Plant via radio telemetry. Touch screen interface panels were replaced; the radio telemetry system was replaced with an Ethernet-based radio telemetry system; and several remote facilities were converted to fiber optic, Ethernet-based communications.
We replaced Supervisory Control and Data Acquisition (SCADA) system human machine interface (HMI) computers and updated the HMI software to the latest version. We installed a new historical archiving and trending software package. We replaced or removed faulty and unused PLC code to improve process controls and documentation.
We installed new PLCs, network switches, touch screen HMI computers, and Ethernet radios in existing control panel enclosures. Portions of the existing fiber optic cabling installed throughout the plant were used along with new fiber optic cable to establish a new self-healing, Ethernet network ring around the facility, which was a significant improvement over the existing line-connected PLCs that would often result in a loss of communication with various control panels if any one panel on the line failed. We sequenced hardware installations so that only one panel was out of service at a time, enabling the plant to continue to operate during construction.
We worked with the plant operations and engineering staff to identify significant improvements that could be made to the existing HMI graphics, focusing on reducing clutter, eliminating extraneous background images, and revising or removing distracting detail from process equipment and piping graphics to make critical information and alarms more visible to operations staff. The City’s local control system integrator programmed all HMI graphics improvements as part of the construction contract through a multi-level review and testing process with the project team.
- Information technology
- Fire protection