The Siemens SIRIUS 3RV2011-0EA20-ZX95 is a motor protection circuit breaker in Size S00 — 45 mm wide, 97 mm deep, 106 mm tall. The breaker carries a 100 kA breaking capacity at 400 V AC, and the same rating holds at 240 V, 500 V, and 690 V AC. For a motor control center or a distribution board fed by a large transformer, this avoids having to coordinate upstream fuses or a bigger breaker for every branch. It also includes phase failure detection, so if one leg of a three-phase supply drops, the breaker trips rather than letting the motor single-phase and burn up. The main circuit connects via spring-loaded terminals, which speeds up wiring in a panel — no screw tightening, just strip and push.
Sizing and selection reality
The breaker is rated for motor protection, but the evidence shows a 0.1 kW rating at 230 V and a 0.4 A rating at 480 V and 600 V. That's a small motor — fractional horsepower, a coolant pump, a small fan, or a conveyor drive under a kilowatt. The AC-3 maximum operating voltage is 690 V, and the maximum switching frequency is 15 operations per hour for AC-3 and AC-3e duty. That's not a high-cycling application; it's a run-of-the-mill motor start once every four minutes or so. The clearance distances are 50 mm upwards and downwards, 30 mm to the side, and zero forwards or backwards. That's the space needed for arc flash venting and heat dissipation — don't cram it against the panel wall or another device without those gaps.
A buyer with a panel designed for the 3RV2011-0BA20: the -0EA20-ZX95 has the same Size S00 footprint, 45 mm width, DIN-rail mounting, and spring-loaded terminals. It will fit without rewiring, but verify the overload setting matches motor FLA.