UNSPSC 39122314: Blocking relay

An auxiliary relay used hinder operation of other relay or equipment under prescribed conditions.

UNSPSC 39122314 Blocking relay (Commodity) covers electrical control components and protective devices that state and local governments procure as components within larger electrical systems, equipment overhauls, and infrastructure projects. Recent state and local solicitations show blocking relays and related protective relays being specified as part of comprehensive electrical modernization, motor control upgrades, and water treatment facility improvements rather than as standalone procurement items. Work under this code typically involves replacement of legacy control systems with current-generation protective relays—including microprocessor-based units from manufacturers such as Schweitzer—integrated into switchgear retrofits, motor control center installations, and programmable logic controller replacements at municipal water districts, county utilities, and special-purpose water authorities.

Issuing bodies soliciting under related electrical control and switchgear scopes span state departments, municipal water districts, county water resources departments, and regional water authorities, with notable recent activity from the Eastern Municipal Water District (Riverside County, California), Orange County (Florida), West Basin Municipal Water District (California), and various city and county utilities. Geographic spread includes California, Florida, Texas, Oregon, and Ohio, with water treatment and utility infrastructure upgrades concentrated in the Southwest and Southeast. Representative recent opportunities include Orange County, Florida's Eastern Water Reclamation Facility (EWRF) Electrical and Mechanical Upgrades (IFB Y26-604, due April 30, 2026), which specified replacement of protective relays with Schweitzer microprocessor-based units as part of 15 kV switchgear modernization; West Basin Municipal Water District's TRWRP 93 Motor Control Center Replacement (RFB RFBTH0120, due March 31, 2026), requiring complete MCC replacement with associated grounding and testing; and Eastern Municipal Water District's medium voltage soft starter installation at Auld Road Booster Station (RFP RFPAR3928, due May 9, 2026), integrating control relays and time delay relay functionality into existing MODBUS RTU systems.