SIRIUS 3RT1024-1AK60 — Size S0 Power Contactor, 7.5 kW Motor Duty
The Siemens SIRIUS 3RT1024-1AK60 is a Size S0 power contactor rated for motor switching at 7.5 kW on 500 V and 690 V supplies, with an AC-4 breaking capacity of 12.5 A at 400 V — meaning it handles reversing or inching duty where the contactor opens under full load, not just steady-state running. It mounts via screw and snap-on onto 35 mm DIN rail per EN 50022, occupying 45 mm of panel width. The front face carries IP20 finger protection; the terminal area is rated IP00, so it expects enclosure protection for the wiring zone. Main and auxiliary circuits use screw-type terminals. For the main contacts, the terminal accepts 2x (1 to 2.5 mm²) solid/stranded or up to 2x 10 mm² maximum. Auxiliary terminals handle 2x (0.5 to 1.5 mm²) solid, 2x (0.75 to 2.5 mm²) stranded, or max 2x 4 mm².
Motor Ratings and Switching Capacity
Rated motor power reaches 7.5 kW at both 500 V and 690 V, 50/60 Hz. AC-2 duty at 400 V is 5.5 kW, covering slip-ring motor starting. The AC-4 rating of 12.5 A at 400 V defines the contactor's capability for plugging or jogging applications — this is the figure that governs real reversing duty, not the higher AC-3 or AC-1 numbers. Auxiliary contact switching capacity is specified across the control voltage range: 10 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 0.3 A at 220 V DC. These values cover both AC and DC pilot circuits for PLC outputs or relay coils.
Coordination and Protection
For Type 2 coordination (no damage to the contactor under short circuit), the required upstream fuse is gL/gG 25 A. For Type 1 coordination (contactor may need replacement after fault), the fuse rating is gL/gG 63 A. These values assume a prospective short-circuit current typical for industrial panels. The contactor is rated for side-by-side mounting without derating, which simplifies panel layout when grouping multiple contactors on the same DIN rail. Operating temperature range is -25 to +60 °C, with pollution degree 3 (conductive pollution expected in industrial environments).
Lifecycle and Compliance
Mechanical endurance is typical 10 million operations. This is the figure for the contactor mechanism itself, not the electrical life under load — electrical endurance depends on switching current, voltage, and duty cycle.