The Siemens 3RV1021-1CA10-ZW96 is a SIRIUS motor protection circuit breaker rated for 2.5 A continuous current with Trip Class 10 thermal overload protection. It provides 100 kA breaking capacity at 400 V AC, covering the most common industrial supply voltage for motor branch circuits. Phase failure detection is built in, so a lost phase trips the breaker before the motor single-phases and burns out.
Mounts via screw and snap-on onto 35 mm standard mounting rail per DIN EN 50022. Width is 45 mm, height 97 mm, depth 96 mm — fits a standard 3-pole MCCB footprint on the rail. IP20 on the front means it's protected against finger contact but not washdown; install inside a rated enclosure. Screw-type terminals for main and auxiliary circuits accept 2x (1...2.5 mm²) solid or stranded, and 2x (2.5...6 mm²) — no special lug kit needed for the larger wire.