The Siemens SIRIUS 3RV2042-4MB10 is a motor protection circuit breaker designed for the main current circuit, with a CLASS 20 trip characteristic that allows it to ride through motor inrush without nuisance tripping — the right curve for standard induction motors driving pumps, fans, and compressors. Phase failure detection is built in, so it catches a lost phase before the motor cooks. Breaking capacity is 100 kA at 400 V AC — that's the interrupting rating at the panel's line side, meaning it can clear a bolted fault at that level without upstream breakers needing to back it up. At 690 V AC the rating drops to 6 kA, so verify the available fault current at the installation point. Mounts on 35 mm DIN rail per DIN EN 60715, with screw and snap-on fastening. Dimensions are 70 mm wide, 165 mm high, 176 mm deep — fits standard motor control center buckets. Screw-type terminals on the main circuit accept 2x (2.5 to 16 mm²) solid or stranded, or up to 70 mm² on a single conductor.
Deployment Context
Snap-on mounting onto 35 mm DIN rail means it integrates directly into a standard motor control center or panel enclosure — no adapter plate needed. The any-position mounting orientation gives flexibility in tight layouts. Operating temperature range of -20 to +60 °C covers most indoor industrial environments; storage range extends to -50 to +80 °C, which matters for cold-chain or unheated warehouse staging before commissioning.