The Siemens SIRIUS 3RV1031-4FB15-ZW97 is a motor protection circuit breaker rated for 40 A continuous current with a CLASS 20 trip curve — meaning it allows a 20-second overload window before tripping, sized for standard induction motor starts on pumps, conveyors, and compressors. Rated 18.5 kW at 400 V AC with a breaking capacity of 50 kA at 400 V and 100 kA at 240 V, this breaker handles fault currents up to those levels without cascading upstream — critical for panel SCCR compliance under IEC 60947-2. Phase failure detection is built in, so a lost phase on the line side trips the breaker before single-phasing damages the motor windings.
Mounting and Wiring
Snaps onto 35 mm DIN rail per DIN EN 50022; screw and snap-on fastening method means no tools needed for the rail, but the main circuit terminals are screw-type with box terminals accepting 2x (0.75... 25 mm²) stranded or 1x (0.75 … 35 mm²) — expect a screwdriver for the power side. Auxiliary and control circuit terminals are also screw-type, accepting 2x (0.5... 1.5 mm²) solid or 2x (0.75... 2.5 mm²) solid — keep the strip length clean to avoid stray strands under the clamp. Dimensions are 55 mm wide by 140 mm tall by 149 mm deep — the 149 mm depth means it projects nearly 15 cm from the DIN rail, so check gland plate clearance if the enclosure is shallow. Mounting position is any orientation, and the front carries IP20 protection — fine for a closed panel, but not for washdown zones.
Lifecycle and Sourcing
RoHS compliance date is July 1, 2006 — the part meets the original RoHS directive, and the substance prohibition date is on record for compliance documentation.
Ratings and Environment
Operating temperature range is -20 to +60 °C, storage and transport from -50 to +80 °C — the storage limit governs handling, not running. Shock resistance rated at 25 g for 11 ms — survives most panel vibration and transport bumps without nuisance tripping. Auxiliary switch is transverse design and the product extension supports an auxiliary switch — the transverse orientation means the switch block mounts alongside the breaker body, not stacked on top. Maximum operating frequency in AC-3 duty is 15 operations per hour — fine for manual or infrequent motor starts, not for high-cycle jogging applications.