What It Is and What It Monitors
The Siemens 3UG5642-1CW31 is a digital monitoring relay that tracks current, active current, voltage, power factor (cos-phi), and active power on a single-phase or three-phase line up to 690 V AC/DC and up to 15 A. It operates from a universal supply of 24 to 240 V AC/DC at 50/60 Hz, making it straightforward to drop into control panels with mixed voltage rails. Both ON-delay and tripping delay are adjustable from 0.1 to 999.9 seconds, which gives you the flexibility to handle inrush currents or transient events without nuisance tripping. The two changeover contacts (2 C/O) provide independent signaling paths for alarm and control logic.
Lifecycle and Sourcing Reality
For compliance documentation, the relay has been RoHS-compliant since June 2023 and carries a REACH Article 33 notification for lead (CAS 7439-92-1) above 0.1% w/w. The export control classification is AL: N / ECCN: 9N9999, meaning no special licensing is required for most destinations.
Integration Notes
The relay uses screw terminals for wiring, which is the standard for panel builders working with ferrule-ended stranded conductors. The packaging dimensions of 127 x 111 x 38 mm fit a typical DIN-rail footprint, and the single-unit packaging means you order per piece for BOM line items. Rated for SIL 1 / PL c, the 3UG5642-1CW31 can be used in basic safety-related monitoring applications where a single-channel architecture with diagnostic coverage is acceptable. This is not a high-integrity safety relay, but it suits conveyor jam detection, pump dry-run protection, or motor load monitoring.