What this part does and where it fits
The Siemens 3RV1902-1AP0 is a SIRIUS undervoltage release — a control-voltage accessory that trips a motor circuit breaker when the supply voltage drops below the coil's dropout threshold. It mounts onto the front of SIRIUS 3RV1/3RV2 circuit breakers in frame sizes S00, S0, S2, and S3, snapping onto the DIN-rail assembly without extra hardware. The coil is rated 230 V AC at 50 Hz and 240 V AC at 60 Hz, so it works across the common industrial line voltages in both frequency regimes. The front face carries an IP20 finger-safe touch protection rating per IEC 60529, which means accidental contact from the vertical direction is blocked — standard for a panel-mounted control device. Auxiliary contacts are not included on this release — zero NO, NC, or CO contacts are built in. If you need status feedback to a PLC or indicator light, you'll add a separate auxiliary switch block to the breaker.
Lifecycle and replacement path
This order code is a phased-out product. The manufacturer's designated successor is the SIRIUS 3RV2902-1AP0, listed as the preferred replacement type. If you're maintaining an existing panel BOM, the 3RV1902-1AP0 is still sourced through independent distribution against an RFQ — availability and current pricing are confirmed at quote time, not from a shelf count.
Physical integration notes
The release measures 90 mm high, 18.5 mm wide, and 68 mm deep. The 18.5 mm width matches the standard single-module DIN-rail footprint — it occupies one 18 mm slot on the rail, leaving adjacent space for other control devices. Operating temperature range is -20 to +60 °C, storage range -50 to +80 °C. The insulation voltage is rated 690 V AC at pollution degree 3, which covers most industrial panel environments with conductive contamination.
Sourcing and compliance
The 3RV1902-1AP0 carries the reference code 'F' per DIN EN 61346-2, which identifies it as a protective device in the functional location standard. For procurement documentation, the product is part of the Siemens SIRIUS family and follows the standard RoHS/REACH compliance framework for industrial control gear — specific certificates are included with the shipment per the order requirements.