What it is and what it does
The Siemens 3RV2011-1JA20-ZX95 is a SIRIUS motor protection circuit breaker designed for motor protection in control panels. It snaps onto 35 mm DIN rail per DIN EN 60715 and uses spring-loaded terminals for the main circuit — no screwdriver needed for the power connections. Trip Class 10 means it clears a locked-rotor condition within 10 seconds at 7.2× the thermal setting — fast enough to protect standard induction motors from overheating during a stall. Phase failure detection is built in, so a lost phase on the line side trips the breaker instead of letting the motor single-phase and burn. Rated operating voltage spans 20 to 690 V AC. Breaking capacity at 400 V is 100 kA — that is a high-fault rating for a 45 mm wide device, meaning it can handle a direct short on a 400 V bus without needing upstream fuses in most panels.
Breaking capacity and motor sizing
Breaking capacity varies by voltage: 100 kA at 400 V, 42 kA at 500 V, and 4 kA at 690 V. The 690 V figure is the weakest link — if your panel feeds a 690 V motor, verify the available fault current is under 4 kA or add a current-limiting device upstream. Motor horsepower ratings are given per voltage: 3 hp at 220/230 V, 5 hp at 460/480 V, and 10 hp at 575/600 V. For a 460 V motor rated 5 hp, this breaker covers the full-load current and the locked-rotor curve within Class 10.
Mounting and clearances
Width is 45 mm — fits a standard 45 mm slot on a DIN rail. Depth is 97 mm, height 106 mm. Required clearances: 50 mm above and below, 30 mm to the side, zero forward or backward. That means you can pack breakers side-by-side with no gap between them, but you need headroom above and below for the arc-chamber venting and terminal access.