What it is and what the ratings mean
The Siemens 3RV2021-1KA15 is a SIRIUS motor protection circuit breaker — the dedicated branch-circuit device for three-phase motor loads. Its CLASS 10 trip characteristic means it opens within 10 seconds under locked-rotor current, fast enough to protect standard IEC motors without nuisance tripping on normal start-up. Breaking capacity is the headline: 100 kA at 400 V and 240 V, 42 kA at 500 V, 4 kA at 690 V. That 100 kA at 400 V means this breaker can safely interrupt a fault up to 100,000 A without welding contacts or cascading failure upstream — essential for high-fault panels near large transformers.
Mounting and integration
Mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, in any position. The 45 mm width (three 15 mm modules) fits standard panel cutouts. Screw-type terminals for the main circuit accept 2x (0.5…1.5 mm²) solid or stranded, or 2x (0.75…2.5 mm²). Rated voltage span is 20…690 V. Ambient operating range -20…+60 °C, storage -50…+80 °C.
Sourcing and lifecycle
Lifecycle stage is current. Sourced and quoted to order against an RFQ through independent distribution.