What this 4 A SIRIUS breaker does on your panel
The Siemens SIRIUS 3RV1011-1EA15-0BA0 is a motor protection circuit breaker rated at 4 A continuous current, with a Class 10 trip characteristic. Its short-circuit breaking capacity hits 100 kA at 400 V AC, so it can sit upstream of a motor starter and safely clear a bolted fault without needing a separate backup fuse — common in high-fault panels like compressor skids or pump stations. The overload release is thermal (bimetal), the short-circuit trip is magnetic — a proven dual-action design that tracks motor heating and clears fast faults independently.
Mounting and wiring — no surprises
Snaps onto 35 mm DIN rail per DIN EN 50022 and accepts screw-type terminals on both main and auxiliary circuits. Solid conductors from 0.5 to 2.5 mm² are supported; stranded from 0.5 to 2.5 mm² as well — no special ferrules required, though they help in repeated disconnect situations. Zero clearance needed at the sides or rear — 0 mm backwards and 0 mm at the side — so you can pack breakers tight in a multi-pole group without derating for airflow blockage. Mounting position is any, which helps when the panel layout forces a horizontal or inverted install on a swing frame.
Auxiliary contact and phase-loss coverage
Built-in transverse auxiliary switch handles 1 A at 24 V, 0.5 A at 230 V, and 0.15 A at 60 V — enough to signal a PLC input or drop out a contactor coil directly. Phase failure detection is included, so a lost phase on the line side will trip the breaker — critical for protecting motors that can single-phase to destruction. The auxiliary switch can be extended with an add-on module if you need more than one N/O + N/C set.