The Siemens 3RV1021-1CA15 is a SIRIUS motor-protection circuit breaker rated for 2.5 A continuous current with a Class 10 trip characteristic, meaning it will trip within 10 seconds at 7.2× the thermal setting — appropriate for standard induction motor starting profiles on pumps, fans, and conveyors. Breaking capacity reaches 100 kA at 400 V AC, so it can safely interrupt fault currents up to that level without cascading upstream — a key spec for high-fault panels where selectivity coordination matters. Phase failure detection is built in, which protects the motor from single-phasing damage — a common failure mode in three-phase lines that a standard thermal overload alone may miss.
Mounting and Integration
Fastens via screw and snap-on onto 35 mm standard mounting rail per DIN EN 50022; any mounting position is permitted, so vertical or horizontal DIN-rail layouts in the panel are equally acceptable. Width is 45 mm, depth 96 mm, height 97 mm — fits a standard 45 mm-wide module slot on the rail; the 0 mm clearance at the side and backwards means it can be mounted flush against adjacent devices without derating. Front IP20 protection covers the operator interface; the screw-type terminals for main and auxiliary circuits accept solid conductors from 0.5 to 2.5 mm² and stranded from 1 to 6 mm².
Lifecycle and Compliance
Operating temperature range is -20 to +60 °C; storage and transport range extends from -50 to +80 °C. Shock resistance is rated at 25g for 11 ms, suitable for industrial environments with vibration.
Ratings and Selection Notes
Auxiliary switch is transverse design and the product extension for an auxiliary switch is available, so you can add a signal contact for remote status indication without a separate interface relay. Maximum operating frequency at AC-3 duty is 15 operations per hour — this is a thermal limit, not a switching-speed limit; for high-cycle applications like rapid reversing, a contactor with a higher rated frequency would be needed. Power dissipation in hot operating state is 7.25 W; factor this into the panel thermal budget when calculating enclosure ventilation.