What this part is and what it does
The Siemens 3RV1011-1FA25 is a SIRIUS motor protection circuit breaker rated for 5 A continuous current with a Class 10 trip characteristic, designed to protect three-phase induction motors up to 1.5 kW at 400 V AC. Its breaking capacity reaches 100 kA at 240 V and 400 V AC, dropping to 3 kA at 500 V and 2 kA at 690 V — meaning it can handle high fault currents on low-voltage distribution but needs coordination upstream at higher voltages. Phase failure detection is built in, so the breaker trips on loss of one phase — a common cause of motor burnouts in unbalanced supply conditions.
Panel integration and mounting
Mounts on a 35 mm DIN rail per EN 50022 using either screw or snap-on fixing, with a 45 mm wide footprint that fits standard distribution boards and motor control centers. Depth is 81 mm, height 90 mm — the 81 mm depth is worth noting for shallow enclosures where cable bend radius behind the breaker is tight. Spring-loaded terminals on the main circuit accept 2x (0.25... 2.5 mm²) solid or stranded conductors (AWG 24...14), so no screw torque verification needed during commissioning. IP20 on the front face means it is protected against finger contact but not against moisture — suitable for dry indoor panels only.
Environmental and mechanical margins
Operating temperature spans -20 to +60 °C, with storage and transport range of -50 to +80 °C — the wider storage range governs handling, not running conditions. Shock rated at 25 g for 11 ms. Main contacts specified for 100,000 mechanical operations. Power dissipation at rated current in hot operating state is 7.25 W — factor this into enclosure thermal calculations when grouping multiple breakers.