Motorola ACE Replacement

Background:

Queensland Urban Utilities had an ageing fleet of Logica MD3311 RTU's which over their service life had been failing on a regular basis. To reduce callouts and replace the legacy hardware, QUU evaluated and decided on the Motorola ACE platform as the new sewage pumpstation standard.

Preliminary Works:

A new Sewage Pumpstation functional spec was developed in conjunction with Witthoft Engineering and QUU staff during numerous stakeholder workshops. From this new functional specification a completely new RTU program, Redlion HMI and Mosaic SCADA was developed with standard code able to take into consideration numerous site options such as:

• Suction and Discharge Pressure Gauges
• Delivery Flowmeters
• Pump DOL/SS & VSD Options
• Generator Onsite options
• Emergency Storage

The standard code handles all these options, with a site specific configuration file enabling or disabling optional equipment as required.

Control System:

A full testbed was setup at QUU premises, with all new code put through its paces. A Citect & GE-Fanuc 90/30 based site was developed to mimic a real pumpstation, with the hardwired signals connected between the GE PLC and the Motorola ACE. Custom Cicode mimiced physical pumpstation operation such as sewage inflow, pump controls, well levels etc.

Cutover:

The pumpstation were changed out while online by Wagtec Engineers. The level in the wet well was monitored and the pumps run in Manual while the RTU was being replaced. Custom wiring harnesses allowed a quick change from the old RTU to the new RTU as the switchboards had umbilical connections between the RTU and the terminal strips. While the RTU was being physically replaced the SCADA was cutover and setup to talk DNP to the new ACE RTU. In total it took around 4hrs per site to physically replace the RTU, then perform a number of standard tests to ensure correct pumpstation operation. In total 138 sites were upgraded by Wagtec staff over a period of approximately 18 months.