Case Study: Metro Wastewater Reclamation District boosts blower uptime with SEL motor protection relays

Utility-Grade Relays Protect Critical Motors at Denver-Area Wastewater Plant

Metro Wastewater Reclamation District, the large Denver-area wastewater plant, needed a more reliable way to protect critical aeration blower motors and keep treatment processes running without interruption in a harsh environment that corrodes electronic equipment. Its aging industrial-grade relays were causing reliability, support, and lead-time problems, creating risk to plant capacity and possible EPA violations; the district turned to Schweitzer Engineering Laboratories (SEL) for utility-grade motor protection relays.

SEL implemented SEL-701 Motor Protection Relays as the standard for Metro’s medium-voltage equipment, along with SEL communication and protection devices integrated into the plant’s control system. The new relays provided stronger durability, more protection and communications features, lower cost, and shorter delivery times than the old equipment. Metro and its engineering partner also standardized on SEL across the site, installing multiple SEL-701, SEL-351, SEL-2030, SEL-587, SEL-501, and SEL-300G devices to improve monitoring, automation, and overall system availability.

Metro Wastewater Reclamation District

Larry Dulworth

Maintenance Planner