All panels were meticulously field documented wire-by-wire, including all field wiring out to the instruments. New drawings were developed for each panel incorporating the upgraded controllers. Cutovers to new controllers were staged one at a time and performed at night when inflow to the plant was at a minimum. I/O cards were pre-wired in our shop to reduce on-site time even further. Each cutover was performed in a single night.
Converted, pre-tested PLC code was loaded by the second integrator, and I/O checkout was jointly performed in the same night. Communication between all parties was handled in a weekly meeting to keep the project on track, and when required, more frequent meetings kept the project running smoothly.
As a result, the owner successfully upgraded the automation in two wastewater treatment facilities to modern controllers that will see them through the next 20 years. The upgrade was performed with no interruption to either facility, and the project finished on time. The 10 upgraded panels and one new remote I/O panel provided are accurately documented, which will be a huge benefit to maintenance and operations moving forward.
