What this contactor is and what it handles
The Siemens SIRIUS 3RT1046-3KB44-0LA0 is an S3-frame power contactor built for motor switching and general load control in industrial panels. It's rated for 80 A in AC-4 duty at 400 V — that's the severe inching and plugging category where contact wear is highest — and delivers 55 kW at 500 V in AC-3 (start-run) service, or 25.4 kW at 690 V. The 24 VDC coil draws 10 A inrush at rated voltage, so size your control transformer and cable accordingly; the coil holds on a clean 24 VDC rail.
Mounting and panel fit
This contactor snaps onto both 35 mm and 75 mm DIN rails — standard for European cabinets — and also accepts screw fixing for vibration-prone environments. Dimensions are 145 mm high by 95 mm wide by 191 mm deep. Side-by-side mounting is supported, so you can gang multiple units without a gap block, but watch the derating when packing tightly: the IP00 front and terminals mean it's intended for enclosed panels, not open air.
Terminal details and wiring
Screw-type terminals on the main circuit accept solid wire 2x (0.25...2.5 mm²) and stranded 2x (10...50 mm²), with a mid-range of 2x (2.5...16 mm²) for solid or stranded. That covers everything from control wiring to motor feeders up to 50 mm². The pollution degree 3 rating means it's suited for industrial environments with conductive dust or occasional condensation — no extra conformal coating needed for typical panel conditions.
Environmental and compliance
Operating temperature range is -40 to +70 °C, storage from -55 to +80 °C, which covers most unheated plant floors and warehouse extremes. The substance prohibition date of 05/01/2012 aligns with RoHS compliance; expect a declaration of conformity covering RoHS and REACH with the shipment.