What it is and what it does
The Siemens 3RV2011-1JA15-ZX95 is a SIRIUS motor protection circuit breaker designed to protect three-phase motors against overload and short-circuit faults. It carries a Trip Class 10 rating, meaning it will trip within 10 seconds at 7.2× the thermal setting — fast enough to protect standard induction motors during a locked-rotor event. The breaker also includes phase failure detection, so if one phase drops out, the unit opens the circuit before the motor single-phases and burns.
Mounting and fit
Mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, in any position. The 45 mm width matches the standard 45 mm modular device footprint — it will sit next to a contactor or relay without overhanging the rail. Depth is 97 mm, so it clears a 100 mm deep enclosure with a few mm to spare for wiring. The M3 main contact screws accept 2× 0.5–2.5 mm² solid or stranded conductors.
Breaking capacity and selectivity
Rated short-circuit breaking capacity hits 100 kA at 400 V — enough for high-fault panels fed by a large transformer. At 690 V it still clears 4 kA, and at 500 V it manages 42 kA. This gives you selectivity headroom downstream: you can coordinate with a feeder breaker without worrying about nuisance trips on a bolted fault.