With the help of MicroMod controllers and software, the Lititz, Pennsylvania Sewer Authority has been awarded the U.S. Environmental Protection Agency(EPA) Region III Operations and Maintenance (O&M) Excellence Award for the Medium Size Advanced Wastewater Treatment category. The Borough’s 3.85 MGD two-stage activated sludge facility is operated and maintained by Severn Trent Services.
Lititz had nine of MicroMod’s 53SL6000 “MicroMite” controllers installed on the return activated sludge, waste activated sludge, intermediate and final clarifiers, and bypass flows, and a set of annunciator panels for 72 alarms and indications. When Severn Trent decided to upgrade the annunciators they chose MicroMod’s MODCELL system because of its single-channel, isolated I/O capability. This feature made MODCELL more attractive than a PLC solution where the multi-channel I/O have a shared common and are more susceptible to electrical spikes and lightning storms.
The MODCELLs and the MicroMite controllers are integrated with MicroMod’s MicroPWC software for graphic operation, trending, and data collection. The system provides indication of dissolved oxygen, influent, and effluent; run time status for pumps, mixers, blowers and other plant equipment; operator access to the controllers from the PC; and trending screens. In addition the mimic panel is duplicated in the MicroPWC workstation. When alarms occur during unmanned periods the system alerts the operator on call via an autodialer, which automatically escalates the alarm call until a response is obtained.