The Siemens 3RT6015-1BM42 is a SIRIUS power contactor in the S00 frame size — the smallest in the SIRIUS contactor family, sized for motor loads up to 10.5 kW at 400 V AC-3 (18 kW at 690 V).
The AC-3 motor-switching rating governs the real-world load: 10.5 kW at 400 V (60 °C ambient) means this contactor handles a standard 400 V three-phase induction motor up to that shaft power. At 690 V it reaches 18 kW, useful for 690 V drives or step-up transformer-fed motors. Mechanical life is 30 million operations typical; electrical life varies by duty cycle — AC-3 maximum switching rate is 750 cycles per hour, AC-4 (plugging/inching) drops to 250 cycles per hour.
Side-by-side mounting is permitted, so multiple contactors can be ganged without spacing. Wire range for main contacts: 2x (0.5–1.5 mm²), 2x (0.75–2.5 mm²), or 2x 4 mm² solid/stranded; AWG equivalents 2x (20–16), 2x (18–14), 2x 12. Minimum conductor size at 40 °C and 60 °C is 2.5 mm² — important for sizing branch-circuit conductors under the NEC or IEC tables.
Auxiliary switch extension is available (product extension auxiliary switch: Yes), so the contactor can be fitted with additional NO/NC blocks for status feedback or interlocking without replacing the base unit. The coil draws 6 A at 24 V rated value, 1 A at 110 V, and 0.3 A at 220 V — check your control transformer sizing if multiple contactors pick up simultaneously.