What it is and what it does
The Siemens 3RV6411-4AA10 is a SIRIUS circuit breaker in size S00, designed specifically for transformer protection. It combines a thermal overload release (Class 10) with a magnetic short-circuit trip, giving you coordinated protection for the inrush and steady-state demands of a transformer primary. Rated 16 A operational current at 690 V AC, 50/60 Hz, it handles the load side of control transformers up to that rating. The Class 10 trip curve means it tolerates the magnetizing inrush without nuisance tripping, while the magnetic trip clears a hard fault fast.
Mounting and integration
Snaps onto 35 mm DIN rail per DIN EN 60715, or screws directly to a panel. The 45 mm width (three 15 mm modules) and 96 mm depth fit standard S00 footprint enclosures. Mounting position is any — no derating required for side or upright orientation. Clearance: 50 mm above and below for airflow and wiring access; zero clearance needed forward or backward. Side clearance is 30 mm. That keeps the panel layout tight without cooking adjacent devices.
Wiring and connections
Screw-type terminals on top and bottom accept 2x (0.75 to 2.5 mm²) solid or stranded, or 2x 4 mm². For AWG, that's 2x (18 to 12) or 2x (20 to 16). Terminal torque: 0.8 to 1.2 N·m. Three poles for the main current circuit.