What this contactor is and where it fits
The Siemens SIRIUS 3RT1017-1AK61-0UA0 is a power contactor in the compact S00 frame size, designed for switching motor loads and resistive loads in control panels. It mounts via screw or snap-on onto a 35 mm DIN rail per DIN EN 50022, and its 45 mm width means it occupies a single modular slot — important when packing multiple contactors side by side, which this unit supports. Rated for AC-2 duty at 5.5 kW at 400 V, this contactor handles slip-ring motor loads where starting current is moderate. For AC-4 reversing or inching duty at 400 V, the rated operational current is 8.5 A — a lower figure that reflects the increased switching stress of plugging and jogging. The coil operates on 50/60 Hz with an operating range of 0.85 to 1.1 times rated voltage at 50 Hz and 0.8 to 1.1 at 60 Hz, so it holds in during brownout conditions down to roughly 85% of nominal. Mechanical life is rated at 30,000,000 operations typical, which for a panel contactor means years of service in a cycling application.
Termination and wiring constraints
Both main and auxiliary circuits use screw-type terminals. The main contacts accept 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or up to 2x (0.75 to 4 mm²) — so you can double up smaller conductors for daisy-chaining, but a single 4 mm² is the max per clamp. AWG equivalents are 2x (20 to 16), 2x (18 to 14), or 1x 12. The auxiliary contacts share the same wire range. Front and terminal faces are rated IP20, so the contactor is protected against finger contact but not against moisture ingress — it belongs inside a sealed enclosure, not in a washdown zone. Pollution degree 3 means it tolerates conductive dust and occasional condensation, typical for industrial control panels.
Short-circuit coordination and protection
For Type 2 coordination (no damage to the contactor after a fault), Siemens specifies a gL/gG fuse of 20 A. For Type 1 coordination (contactor may be damaged but no fire or shock risk), the fuse rating is 35 A. These values matter when designing a panel for selectivity — the upstream fuse must clear a fault before the contactor welds.
Lifecycle and sourcing posture
The product carries a substance prohibition date of 01.07.2006, which aligns with the original RoHS directive. For current RoHS/REACH declarations, the manufacturer provides compliance documentation with each shipment.