What it is and what it does
The Siemens 3RV1021-0DA10-ZW97 is a SIRIUS motor protection circuit breaker — a 3-pole device sized for the low end of the motor branch. It carries a 0.32 A continuous current rating and trips CLASS 10, meaning it clears an overload before the motor windings reach their thermal limit under locked-rotor conditions. Phase failure detection is built in, so a lost phase on the line side drops the load before single-phasing cooks the motor.
Breaking capacity and voltage ceiling
Rated breaking capacity holds at 100 kA across the board — 240 V, 400 V, 500 V, and 690 V AC — so it handles high-fault utility feeds without cascading upstream. The maximum operating voltage hits 690 V AC-3, which covers 400 V and 480 V line-to-line systems with headroom. That 100 kA SCCR at 400 V means this breaker can sit on a panel fed by a transformer with a stiff secondary and still coordinate.
Panel fit and mounting
Mounts on 35 mm DIN rail per EN 50022 — screw and snap-on, no tools for the rail engagement. The footprint is 45 mm wide, 97 mm tall, 96 mm deep, so it takes one standard 45 mm slot in a distribution board. Terminal wiring accepts solid or stranded conductors: 2x (1 to 2.5 mm²) and 2x (2.5 to 6 mm²) per pole, screw-type. That covers most motor feed cables up to 6 mm². Auxiliary switch can be added on the side; the breaker is prepared for it.
Environmental and compliance
Operating temperature range is -20 to +60 °C; storage and transport handle -50 to +80 °C. Shock rated at 25g for 11 ms. Front protection is IP20 — finger-safe but not washdown-rated. RoHS compliance date is 01.05.2012, and the lifecycle status is current, so this is an active catalog line, not a phase-out. Compliance documentation (RoHS, REACH, UL, IEC) is available from Siemens for this SIRIUS series.