The Siemens 3RV2811-1FD10 is a SIRIUS-brand circuit breaker in the S00 frame size, explicitly designed for transformer protection and listed to UL 489 / CSA C22.2 No. 5. That UL 489 listing means it's certified as a branch-circuit protective device for North American panels, not just a European-style motor-protective switch. The S00 frame keeps the footprint compact at 45 mm wide and 144 mm tall, and it mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715 — standard for any control panel enclosure.
SCCR and selectivity — the numbers that matter
The interrupting rating tells you where this breaker can sit in a fault-current hierarchy. At 400 V AC it clears 100 kA — that's a high-capacity distribution board or a transformer secondary with stiff utility feed. At 690 V AC the rating drops to 6 kA (AC) or 4 kA (unconditional), which is typical for the voltage step; you'd coordinate it upstream of a current-limiting fuse or a higher-rated MCCB. The gG fuse coordination values are also listed: at 400 V and 500 V the maximum gG fuse is 32 A, at 690 V it's 25 A. That's the fuse size the breaker's let-through energy is designed to coordinate with for back-up protection.
The screwdriver shaft diameter is 5 to 6 mm with a Pozidriv size 2 tip. The M4 main-contact screws are standard for the S00 frame.