SIRIUS S00 power contactor with spring-loaded terminals
The Siemens SIRIUS 3RT1015-2GG28-0NA4-ZX95 is a size S00 power contactor rated for motor switching at 4 kW at 690 V AC-3 and 3.5 kW at 500 V AC-3. The main current circuit uses spring-loaded terminals accepting 2x (0.25... 2.5 mm²) solid or stranded wire, which speeds panel wiring compared to screw terminals and holds up better under vibration. The contactor mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022, with a 45 mm width and 60 mm height, fitting standard panel layouts. Side-by-side mounting is permitted without derating, so multiple contactors pack tightly on the rail. The integrated surge suppressor uses full-wave rectification, meaning the coil drive includes a built-in suppression circuit that handles the inductive kick without requiring an external varistor or RC snubber. This simplifies wiring and reduces panel clutter.
Ratings and what they mean for your load
The AC-3 rating of 4 kW at 690 V defines the motor-switching capability for squirrel-cage motors — starting and disconnecting under load. At 500 V the same duty yields 3.5 kW. For resistive or lightly inductive loads (AC-1), the contactor handles up to 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V. These are the currents the main contacts can make and break without excessive wear. The AC-4 rating of 6.5 A at 400 V covers inching and plugging duty — frequent starts and reversals that generate more arc energy than AC-3. If your application involves jogging or reversing under load, this is the rating to size against. The contactor is rated for pollution degree 3, meaning it tolerates conductive dust and humidity typical of industrial control panels without conformal coating. Operating temperature spans -25 °C to +60 °C, with a maximum altitude of 2 000 m.
Panel integration and wiring
Front protection is IP20, so the contactor is safe for finger contact in an enclosed panel but not for washdown environments. The auxiliary contact block (1 N/O instantaneous) is integrated, and the terminal design allows for solid or stranded wire up to 2.5 mm² (AWG 14). For type 2 coordination, the required upstream fuse is gL/gG 20 A — this limits let-through energy so the contactor survives a short circuit without welding its contacts. The clearance to adjacent components on the side is 6 mm.