What it is and what it does
The Siemens SIRIUS 3RV2011-0FA20-ZX95 is a motor protection circuit breaker in the S00 frame size, designed to protect motor branches against overload and short-circuit in a single device. It is rated for CLASS 10 trip characteristics, which means it disconnects within 10 seconds at 7.2× the thermal setting — fast enough to protect a standard induction motor winding before insulation damage sets in. The breaker carries a 100 kA breaking capacity at 400 V AC, making it suitable for installation at the motor branch where fault current levels can be high. Phase failure detection is built in, so a lost phase on the line side trips the breaker — no separate phase-loss relay needed.
Mounting and panel fit
Mounts via screw or snap-on onto a 35 mm DIN rail per DIN EN 60715. The S00 footprint is compact: 45 mm wide, 97 mm deep, 106 mm tall. Clearance requirements are 50 mm above and below, 30 mm to the side, and zero forward or backward — so a panel layout with 50 mm wireway above and below the rail is sufficient.