What this breaker is and where it lands
The Siemens 3RV2011-1BA10-ZX95 is a SIRIUS motor-protection circuit breaker designed for protecting three-phase induction motors against overload and short-circuit faults.
At 400 V AC the 3RV2011-1BA10-ZX95 interrupts 100 kA, and at 690 V it still holds 10 kA. At 690 V the 10 kA rating still covers most industrial motor branch circuits; only very high-fault installations would need an upstream current-limiting device. The gL/gG fuse backup ratings are 25 A at 400 V and 500 V, dropping to 20 A at 690 V — these are the maximum upstream fuse sizes that still allow the breaker to achieve its full interrupting rating. If your panel already has a 25 A gG fuse ahead of this breaker, you're covered up to 500 V.
Mounting and clearances — panel fit
Required clearances: 50 mm above and below for arc-chamber venting, 30 mm to the side, and zero forward or backward clearance needed. That zero-backwards spec means it can sit flush against a backplate or gland plate without derating. Mounting position is any orientation, so vertical or horizontal rail placement works. The screw terminals accept 2×(0.75–2.5 mm²) solid or stranded, or 2×4 mm² — enough for the motor feeder on a 0.13 hp (230 V) to 1 hp (460/480 V or 575/600 V) motor.