Water Utility PLC Upgrade

A large water utility plant required services to upgrade their systems whilst maintaining a few of their system assets. Current setup included a redundant RX7i PLC installed more than 20 years previously.

Project Scope

Due to the lifecycle status of the product, there was a need to upgrade the Pump Station Controller. Based on the need to keep the mature GE 90-30 PLC IO assets in place, and review by one of their consultants against other PLC solutions in the market, the GE RX3i upgrade solution was chosen.

A simplified scope of the project was:

  • Access existing code, hardware and site factors to ensure correct RX3i hardware is chosen to replace existing RX7i Redundant PLC and keep existing 90-30 hardware onsite
  • Procure new RX3i hardware and upgrade software for testing offsite
  • Upgrade existing drawings
  • Site commissioning


The system integrator worked closely with the application team at GE and Control Logic Application Engineers to ensure some of the below application issues were discussed and reviewed.

  • The existing panel sizes for the new equipment
  • The changes required to be made into existing logic
  • Hardware that could be used in the older versions of programming software
  • Confirm if there was no need to upgrade the remote I/O 90-30s and five 90-30 CPUs onsite at the same time.

Based on further investigation, the CPE330 was the best RX3i CPU for redundancy for this project. Due to the customer utilising an older version of the programming software and not being in a position to upgrade software, the CPE330 is easily configurable to work with the older redundant CPR320 CPU.



For more information on GE’s range of PLCs, or this case-study please contact Control Logic on 1800 557 705 or by emailing our product specialists at sales@controllogic.com.au.