SIRIUS S0 power contactor — what the ratings mean for your panel
The Siemens 3RT1024-1AU60 is a SIRIUS-branded power contactor in the S0 frame size, carrying three normally-open main contacts and screw-type terminals for the main current circuit. It mounts on a 35 mm DIN rail per DIN EN 50022, using either screw or snap-on fixing, which is the standard integration for a control-panel builder — no adapter plate needed, and the 45 mm width leaves room for a three-phase motor starter combination alongside an overload relay in the same S0 footprint. The headline motor-switching rating is 7.5 kW at 400 V in AC-3 duty, which is the standard induction-motor category — that means it handles the inrush of a 15 A motor on a 400 V line without welding the contacts. For reversing or plugging duty (AC-4), the rated operating current is 12.5 A at 400 V, a lower figure because the contacts must interrupt full-load current at each reversal. If your application calls for Type 2 coordination — no damage to the contactor on a short-circuit fault — the required upstream fuse is 25 A gL/gG; Type 1 coordination allows a 63 A fuse, which will destroy the contactor but clear the fault. The contactor is rated for an operating temperature range of -25 to +60 °C and a maximum operating altitude of 2 000 m. Pollution degree 3 means it's suitable for industrial environments where conductive pollution can occur — typical for a panel in a factory hall, not a clean room. The front face carries IP20 protection, so the terminals are finger-safe once the panel door is closed; the terminal body itself is IP00, which is normal for a contactor that lives inside a locked enclosure.
Integration — DIN rail, wiring, and clearances
The contactor occupies a 45 mm width on the DIN rail, with a depth of 91 mm and height of 85 mm. Side-by-side mounting is permitted with a 6 mm clearance at the side — no forced spacing between units if the thermal load allows. The screw terminals accept solid or stranded conductors: main contacts take 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or up to 2x (0.75 to 4 mm²); the auxiliary/coil terminals are not separately listed but the main circuit terminal range covers the typical control wiring sizes. AWG equivalents are 2x (16 to 12), 2x (14 to 10), and 1x 8.