What this 0.16 A SIRIUS breaker does on the line
The Siemens 3RV1021-0AA10 is a SIRIUS motor protection circuit breaker rated for 0.16 A continuous current with a 100 kA breaking capacity across 240 V to 690 V AC. That 100 kA SCCR means it can safely interrupt a bolted fault up to that level without the upstream device needing to clear it — critical for panel coordination in high-fault industrial plants. Trip Class 10 gives it a 10-second maximum trip time at 7.2× rated current, fast enough to protect standard induction motors during stall without nuisance tripping on normal starting inrush. Phase failure detection is built in, so a lost phase on the line side drops the load before single-phasing cooks the winding.
Mounting and panel fit
Mounts via screw or snap-on onto 35 mm standard rail per DIN EN 50022. The 45 mm width and 96 mm depth keep it to a single modular unit on the rail — no extra side clearance needed (0 mm backwards, 0 mm at the side). Any mounting position works, so it fits tight enclosures or vertical bus drops. Screw-type terminals on both main and auxiliary circuits accept up to 6 mm² solid or stranded, with dual-wire entry for looping through.
What the ratings mean for your panel
The 100 kA breaking capacity at 400 V is the headline number — it matches the typical utility fault current at a low-voltage service entrance, so this breaker can be the first device after the main disconnect without needing a current-limiting fuse upstream. The 0.16 A continuous rating is the motor FLA it protects; pair it with a contactor rated for the same motor current. Power dissipation runs 5.5 W hot (1.8 W per pole), so thermal rise in a dense panel stays manageable. IP20 on the front means finger-safe from the front but not sealed against dust or moisture — keep it inside a rated enclosure.