The Siemens 3RV1021-0GA15-ZW95 is a SIRIUS motor protection circuit breaker rated for 0.63 A continuous current with a CLASS 10 trip characteristic. Breaking capacity holds at 100 kA across the 240 V to 690 V AC range, so it safely interrupts fault currents up to that level without cascading upstream — a key spec for high-SCCR panel designs where the main breaker isn't oversized for the branch. Phase failure detection is built in, which prevents single-phasing damage on three-phase motor loads — a common failure mode in field-aged contactors or loose supply connections.
Mounting and integration
Mounts via screw and snap-on onto 35 mm standard mounting rail per DIN EN 50022, so it clips into the same DIN profile as the rest of the SIRIUS contactor and overload range — no adapter plate needed. Dimensions are 45 mm wide × 97 mm high × 96 mm deep, occupying a single 45 mm module on the rail. The IP20 front protection means it's safe for finger-probe access inside a closed panel but not for washdown environments. Screw-type terminals on the main circuit accept solid conductors 2×(0.5…1.5 mm²) and 2×(0.75…2.5 mm²), or stranded 2×(1…2.5 mm²) and 2×(2.5…6 mm²) — covers standard panel wire up to 6 mm² for the load side.
Environmental and mechanical ratings
Operating temperature range is -20 to +60 °C, storage and transport range -50 to +80 °C — suitable for unheated plant floors and cold warehouses as long as the ambient stays above -20 during operation. Shock resistance rated at 25 g for 11 ms, and the mechanical endurance of the main contacts is 100 000 cycles typical — enough for frequent-start applications like conveyors or compressors. Maximum altitude for rated operation is 2 000 m; above that, derating applies for air insulation and cooling.