The Siemens SIRIUS 3RT1034-3AN60 is a size S2 power contactor with screw-type terminals on the main circuit, rated for 18.5 kW at 500 V AC-3 duty.
AC-3 switching at 400 V is rated for 15 kW — that's the motor-switching duty most often specified. AC-1 resistive load maxes at 1200 operations per hour, while AC-3 allows 1000 ops/h, and AC-4 (inching/plugging) drops to 250 ops/h. The mechanical life is a typical 10 million operations. For auxiliary contact ratings: 24 VDC carries 10 A, 60 VDC carries 2 A, and 230 VAC carries 6 A. The arcing time runs 10 to 15 ms, and the coil operates across 0.8 to 1.1 times rated voltage at 50 Hz and 0.85 to 1.1 at 60 Hz.
Main circuit screw terminals accept solid wire 2x (0.25 to 2.5 mm²) and stranded wire 2x (0.75 to 25 mm²). The auxiliary/control terminals accept solid or stranded 2x (0.75 to 16 mm²). These are standard cage-clamp-style screw terminals — torque per the markings on the contactor. The IP00 terminal area means the live parts are exposed; panel builders need to cover or segregate per the enclosure's IP rating.
No successor has been published. If you're stocking spares for a line that uses the SIRIUS S2 frame, this contactor is a standard, broadly stocked item — a fast mover worth keeping on the shelf at min/max levels.