What this SIRIUS motor protection circuit breaker is
The Siemens 3RV1011-1KA10-0FJ0-ZX95 is a SIRIUS-branded motor protection circuit breaker rated 12 A continuous current, with a CLASS 10 trip characteristic. The unit carries a 5.5 kW motor rating at 400 V AC, and its interrupting capacity reaches 50 kA at 400 V AC — enough to handle high-fault-current industrial panels without needing upstream current-limiting fuses in most installations.
Mounting and panel integration
Mounts via screw or snap-on onto 35 mm standard mounting rail per DIN EN 50022. The 45 mm width (3 module spaces) and 81 mm depth mean it fits standard distribution boards. Zero clearance required at the back or sides — you can butt it against other devices or the enclosure wall without derating for heat dissipation. Mounting position is any orientation, which simplifies panel layout in tight cabinets. Operating temperature range is -20 to +60 °C, storage and transport from -50 to +80 °C.
Termination and wiring
Main circuit connections use screw-type terminals. Solid and stranded conductors: 2× (0.5 to 1.5 mm²) or 2× (0.75 to 2.5 mm²). Finely stranded with ferrule: same ranges. AWG equivalents: 2× (18 to 14). The dual-conductor capacity is useful when looping through to a contactor or another device without a separate terminal block.
Protection features and ratings
Phase failure detection is built in — the breaker will trip if one phase is lost, preventing single-phasing motor damage. Ground fault detection is not included. The auxiliary switch is present (yes), but no auxiliary contacts are pre-fitted (0). Rated insulation voltage is 690 V, with a surge voltage resistance of 6 kV. Maximum operating altitude is 2 000 m without derating. Shock resistance: 25 g for 11 ms. Mechanical endurance: 100 000 operations typical. Power dissipation at rated current in hot operating state: 9.25 W total, 3.1 W per pole. Maximum switching frequency in AC-3 duty is 15 operations per hour.