The Siemens 3UG5512-1BR21 is a line monitoring relay that watches three-phase mains for phase failure, phase sequence reversal, and asymmetry — the three faults that stall a motor or cook a drive input stage. It accepts 3x 160-690 V AC, 15-70 Hz, so it covers 208 V through 600 V class systems without a separate PT. Two changeover contacts give you a healthy signal and a trip output on separate circuits, which is handy for a PLC input plus a local alarm lamp. Rated SIL 1 / PL c, meaning it can serve in basic safety functions where the risk reduction is modest — think monitoring a pump motor before a manual reset, not a press guard. The screw terminals are standard for panel wiring; no special tooling needed.
RoHS compliance effective June 2023, with REACH Article 33 disclosure for lead above 0.1% w/w (CAS 7439-92-1). No export restrictions (AL: N / ECCN: N).
RoHS compliant since June 2023. REACH candidate list substance: lead (CAS 7439-92-1) > 0.1% w/w — disclosed per Article 33. No UL or CSA listing appears in the spec record; the part carries CE marking for the European market.