The Siemens SIRIUS 3RT1024-1BE44 is a power contactor in the S0 frame size, designed for switching motor loads and resistive circuits in industrial control panels. It mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 50022, and the 45 mm width fits standard panel layouts. The 24 VDC coil draws 5.4 W during both closing and holding, so the control transformer sizing is straightforward — no inrush spike beyond the steady-state power. Front-face protection is IP20; the terminal area is IP00, meaning the wiring compartment expects enclosure protection from the panel.
Switching Ratings and Duty Cycles
The contactor's switching capacity varies by voltage and load type. At AC-12 (resistive) it handles 10 A maximum. For motor duty, the AC-3 rating at 690 V delivers 7.5 kW, and at 400 V the same 7.5 kW applies. The AC-4 rating — the severe reversing or inching duty — is 12.5 A at 400 V, which is the figure to watch for jogging applications. DC switching is also specified: 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V. The mechanical life is rated at 10 million operations typical, per the datasheet.
Short-Circuit Coordination and Wiring
For Type 2 coordination (no damage to the contactor after a fault), the required upstream fuse is gL/gG 25 A. For Type 1 coordination (contactor may need replacement but no hazard), the fuse can be 63 A. The main circuit terminals accept screw-type connections: solid or stranded wire from 1 to 6 mm² (2x conductors), with a maximum of 2x 10 mm². The auxiliary contact block includes 2 instantaneous contacts. Pollution degree 3 is specified, meaning the part is rated for conductive pollution environments typical of industrial panels.
Environmental and Mounting
Operating temperature range is -25 to +60 °C. Maximum operating altitude is 2,000 m without derating. Side-by-side mounting is permitted with 6 mm spacing on either side. Dimensions are 85 mm height, 45 mm width, and 150 mm depth — the depth is the dimension to check against enclosure depth when the contactor is rail-mounted with wiring ducts. The reference code per DIN EN 81346-2 is Q (power switching device).