What it is and what it does
The Siemens 3RV2011-1AA20-ZX95 is a SIRIUS motor protection circuit breaker designed to protect motors against overload and short-circuit. It trips in Class 10, meaning it clears an overload within 10 seconds at 7.2× the thermal setting — fast enough to protect standard induction motors during a locked-rotor event. The breaker carries a 100 kA breaking capacity at 400 V AC, so it can safely interrupt fault currents up to that level without upstream fuses needing to clear first.
Mounting and wiring
Mounts on 35 mm DIN rail per DIN EN 60715 using either the screw or snap-on method. The 45 mm width fits standard panel spacing. Spring-loaded terminals on the main circuit accept 2× (0.5 to 4 mm²) solid or stranded wire — no screw torque to verify, just strip and push. Any mounting position works, but leave 50 mm clearance above and below, 30 mm to the sides, and zero forward clearance needed.