The Siemens SIRIUS 3RV2031-4BA10-ZX95 is a motor protection circuit breaker designed for Class 10 trip response, meaning it will disconnect within 10 seconds at 7.2× the thermal setting — fast enough to protect standard induction motors during locked-rotor events without nuisance tripping on normal starts. Breaking capacity is 100 kA at 240 V, 30 kA at 400 V, 6 kA at 500 V, and 3 kA at 690 V — the 400 V figure is the one that governs most European 400 V line-side installations, and it provides ample SCCR headroom for typical panel coordination.
This part carries a lifecycle status of current production, so it remains available through the standard Siemens SIRIUS channel.
Key Protection Features
Ground fault detection is not included, so if that is required, an external ground-fault module or a different SIRIUS variant would be needed. Rated operational voltage spans 20 to 690 V, covering low-voltage motor circuits from 24 V control transformers up to 690 V industrial mains.
Dimensions are 55 mm wide, 140 mm high, 149 mm deep — a standard SIRIUS 3RV2 footprint that fits alongside contactors and overloads on the same DIN rail. Main circuit terminals accept screw-type connections: 2× (1 to 25 mm²) or 1× (1 to 35 mm²) solid or stranded, with M6 terminal screws. Maximum switching frequency in AC-3 duty is 15 operations per hour, which suits motor starting cycles for pumps, fans, and compressors — not high-speed jogging or reversing applications.