What it is and where it fits
The Siemens 3RT1015-2BM41 is a SIRIUS power contactor in the compact S00 frame size, designed for switching motor loads and resistive circuits in industrial control panels. It mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022, and its 45 mm width means it occupies a single 45 mm module slot — that's another SKU I don't need to guess about for panel layout. Rated coil voltage is 220 V AC; pick-up voltage is 85 % of rated (187 V), drop-out at 110 % (242 V). Coil holding power is 3.3 W DC, same as closing power — a low-hold design that keeps heat down in a crowded enclosure. Spring-loaded terminals on the main circuit accept 2x (0.25 to 2.5 mm²) solid or stranded, or 2x (24 to 14 AWG).
Ratings and what they mean for your load
The contactor is rated for AC-2 duty at 400 V at 3 kW — that's the standard for slip-ring motor starting. For AC-4 (plugging / inching) at 400 V it carries 6.5 A. For resistive loads (AC-12) the maximum operating current is 10 A. The auxiliary contact block provides 1 normally-open instantaneous contact. Switching capacity for DC loads: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.3 A at 220 V. That covers most solenoid and small DC motor loads in a panel. For AC loads at 230 V it handles 6 A; at 400 V, 3 A. Motor power ratings: 3.5 kW at 500 V, 4 kW at 690 V. The size S00 frame is typically used for motors up to about 5.5 kW at 400 V — this part covers the lower end of that range cleanly.
Integration and environment
Side-by-side mounting is allowed with zero gap — the 6 mm side clearance is only needed for heat dissipation near thermal limits. Ambient operating range is -25 to +60 °C, with pollution degree 3. IP20 on the front and at the terminals. Maximum operating altitude is 2 000 m without derating. Mechanical life is 30 million operations — that's the contactor body itself; electrical life depends on the load and switching frequency. Short-circuit coordination: for Type 2 (no damage to the contactor) use a gL/gG fuse rated 20 A; for Type 1 (contactor may need replacement) use 35 A. The reference code per DIN EN 81346-2 is Q (switching device).