The Siemens 3RT1044-3EL24 is a SIRIUS S3 power contactor — the S3 frame size sits between the compact S2 and the larger S6 in the SIRIUS family, sized for motor switching and resistive loads in industrial control panels. It mounts via screw or snap-on onto 35 mm and 75 mm standard DIN rails, with side-by-side mounting permitted, so you can pack multiple contactors in a row without derating for heat buildup. The coil is 24 VDC — a common control voltage across PLC and relay logic panels. Rated operating range at 50 Hz is 0.8 to 1.1 times rated voltage, and at 60 Hz it's 0.85 to 1.1, so the coil holds in through brownout conditions down to about 19.2 VDC. Dropout typically occurs below 18 VDC, which is standard for this class.
Terminal and enclosure details
The main power terminals accept 2x (10... 50 mm²) stranded wire — that's a big lug range, covering everything from 8 AWG up to 1/0 AWG depending on the termination method. The control/auxiliary terminals take 2x (0.25... 2.5 mm²) solid or 2x (2.5... 16 mm²) stranded, which covers standard control wiring. The front of the contactor is IP20 with a cover or box terminal; the terminal body itself is IP00, so the panel enclosure provides the overall ingress protection. Pollution degree 3 per IEC 60947-1 — that's the typical industrial environment rating: conductive pollution or dry non-conductive pollution that becomes conductive due to condensation. It means the contactor is designed for the usual panel conditions, not for clean rooms or sealed electronics cabinets without consideration of condensation.
Environmental and mechanical ratings
Operating temperature range is -25 to +60 °C, storage from -55 to +80 °C. The storage range is wider because the contactor isn't switching loads in storage — that limit governs handling and warehousing, not running. Mechanical shock resistance is 10.6 g for 5 ms and 6.2 g for 10 ms on AC, with DC arcing time of 14 to 20 ms. Those numbers matter if the contactor is mounted near heavy switchgear or on a mobile platform. Dimensions: 163 mm high, 70 mm wide, 188 mm deep. The 188 mm depth includes the arc chamber and terminal overhang — check your enclosure depth if you're retrofitting into a shallow panel. Typical mechanical life is 10 million operations, which is standard for an S3 frame contactor in this class.