What it is and where it fits
The Siemens 3RT1374-6AR36 is a SIRIUS contactor in size S12, designed for switching motor loads and resistive loads in industrial control panels. It mounts via screw fixing on a vertical surface, with flexibility to be rotated ±180° or tilted forward/backward up to 30° at 0° rotation, or used standing. The 225 mm height, 184 mm width, and 180 mm depth define the panel space it occupies; clearance distances of 10 mm upwards, 10 mm downwards, 10 mm at the side, and 20 mm forwards are needed around it for heat dissipation and arc containment.
Coil and control circuit
The magnet coil is AC-operated with screw-type terminals, rated for a control supply voltage of 250 to 500 V AC at both 50 Hz and 60 Hz. Coil power consumption is 21 VA at either frequency. The pickup voltage ratio is 0.8 (initial value), and the dropout voltage ratio is 1.1 (full-scale value), meaning the contactor picks up at 80% of rated voltage and drops out at 110% — standard for AC coils to ensure reliable pull-in under brownout conditions. Operating times are 45 to 80 ms for both AC and DC switching.
Main and auxiliary contacts
The contactor carries 2 instantaneous auxiliary contacts and includes an auxiliary switch. Up to 2 additional auxiliary contacts can be attached. Rated operational current varies by voltage: at 24 V it is 3 A, at 48 V it is 1.5 A, at 110 V and 125 V it is 0.55 A, at 220 V it is 0.3 A, at 230 V it is 4 A, at 400 V it is 3 A, at 500 V it is 2 A, and at 690 V it is 2 A. These values reflect the switching capacity across different control and auxiliary circuits — the 230 V and 400 V ratings are the highest, typical for motor control applications.
Environmental and wiring specs
Operating temperature range is -40 to +60 °C; storage range is -40 to +70 °C, covering most industrial environments from cold storage to warm cabinets. The screw terminals accept solid or stranded conductors: 1x (1 to 4 mm²) or 2x (1 to 4 mm²) per clamp, which covers standard control wiring up to 12 AWG.