The Siemens 3RT2018-2BE41 is a SIRIUS S00 power contactor — the smallest frame size in the SIRIUS family, sized for motor loads up to around 3 kW at 400 V AC-3. The 24 VDC coil is terminated with spring-type terminals, so no screwdriver is needed for the control wiring — just strip 8 mm and push in. The main contacts accept 0.5 to 4 mm² solid or stranded wire, and dual-wire termination (2x 0.5–4 mm²) is allowed on each clamp.
The DC switching capability is specified at multiple voltages: 10 A at 24 V, 2 A at 48 V and 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, and 3 A at 400 V. These are the maximum resistive-load currents the contacts can interrupt at each voltage level — a critical selection point for DC motor brakes, solenoid valves, or any DC auxiliary circuit in the panel. For AC motor duty, the contactor is rated at AC-3 (750 operating cycles per hour maximum) and AC-4 (250 ops/h). The AC-3 rating governs normal motor starting and running; the AC-4 limit applies when the contactor must break the motor at full load — inching or plugging applications. At AC-1 (resistive loads) it can manage 1,000 ops/h.
Mounting and Clearance — No Surprises
The contactor measures 45 mm wide, 70 mm tall, and 73 mm deep. Minimum clearance to adjacent components: 10 mm upward and forward, 10 mm downward, 6 mm to the side.
This part carries a current production lifecycle status — it is still in active manufacture by Siemens.