Integrator's spec recap
The Siemens 3RT2018-2EK61 is a SIRIUS power contactor in Size S00 — the smallest frame in the SIRIUS family, sized for motor loads up to about 7.5 kW at 400 V (AC-3). It measures 45 mm wide by 70 mm tall by 73 mm deep, fitting a single 45 mm DIN-rail slot. The coil terminals are spring-type (push-in), accepting solid or stranded wire from 0.5 to 4 mm², and up to 2x (0.5 to 4 mm²) per clamp. An integrated auxiliary switch is included, rated for 10 A at 24 V, 2 A at 48 V, 1 A at 110 V, 0.3 A at 220 V, and 3 A at 400 V — covering most control-voltage levels in a single block. Mechanical life is rated at 30 million operations typical. Maximum switching frequency varies by duty: 1000 ops/h for AC-1 (resistive), 750 ops/h for AC-2 and AC-3 (motor starting), and 250 ops/h for AC-4 (plugging/inching). The arcing time is 10 to 15 ms at AC. Coil power loss is 0.24 W at both 50 and 60 Hz.
Panel integration & clearances
Mounting is by screw or snap-on onto 35 mm DIN rail per DIN EN 60715. The mounting position is flexible: +/-180° rotation on a vertical surface, and can be tilted forward/backward by +/-22.5° on a vertical surface. Required clearances around the contactor: 10 mm upwards, 10 mm downwards, 10 mm forwards, and 6 mm at the sides. Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C.