Harris Group provided systems integration services for the Bio-Solids Facility at the Tri-City WWTP facility located in Clackamas, Oregon. The Bio-Solids Facility is composed of the following equipment:

• Andritz centrifuge system which includes the triple head polymer injector, lubrication unit, centrifuge rotating assembly, backdrive system, centrifuge starter panel, cake conveyors and cake hopper.
• Two gravity belt thickeners (GBT).
• Two US Filter Polymer Control Systems.
• Associated balance of plant pumps, motors, equipment and instrumentation.
• Video operation surveillance system

Systems integration services included assisting with the testing, commissioning, and startup of the Bio-Solids Facility. Plant HMI SCADA (Wonderware) and PLCs were reprogrammed to interface to the Andritz and US Filter Control Systems. Supporting PLC and HMI programming was performed to assist Andritz and US Filter using S7 Siemens Programmable Logic Controllers (PLC).

In addition to the PLC, the Control System consisted of two Siemens OP-3 operator stations that interface to the Polymer system. Two PanelView operator terminals, panels that each controls their corresponding Gravity Belt Thickener (GBT) and Wonderware centrifuge terminal.

The Control System communication consists of two separate networks. A field network that communicate via Profibus, and SCADA/TI Ethernet network. The S7 PLC's communicate via Profibus-DP. Field instrumentation resided on a Profibus-PA network while the S7 was interfaced to the Motor Control Centers via Profibus-to –Devicenet modules.