The Siemens 3RV1922-1CP0 is a SIRIUS undervoltage release designed for use with motor circuit breakers in sizes S00, S0, S2, and S3. The coil is rated for 230 V AC at 50 Hz and 240 V AC at 60 Hz, so it's suited for 230/240 V line-to-neutral control circuits common across European and North American panels.
The release carries 2 NO (normally open) leading auxiliary contacts — these close when the release is energized and open on undervoltage, providing a positive status signal to the PLC or safety relay. The leading-contact design means the auxiliary contacts change state slightly ahead of the main contacts, which is useful for signaling readiness before the breaker closes. Snap-on mounting onto a 35 mm DIN rail per EN 50022 keeps installation straightforward; the 18.5 mm width means it occupies a single 18 mm modular slot, and the 68 mm depth fits standard enclosure depths without crowding the gland plate. IP20 finger-safe protection on the front (per IEC 60529) allows vertical contact from the front without risk of shock, which is the minimum for a panel-mounted control device.
The 3RV1922-1CP0 is a phased-out product. The official Siemens successor is the 3RV2922-1CP0, which is the preferred replacement type. If you're planning a new panel build, the successor is the cleaner path; for a line-down replacement on an existing panel, this part remains available through the surplus and broker channel.