The Siemens 3RT1034-1AP60 is a SIRIUS power contactor in the Size S2 frame, rated for motor switching at 18.5 kW at 500 V in AC-3 duty.
The headline motor rating is 18.5 kW at 500 V (AC-3), which covers common 400 V class motors at 15 kW as well — the AC-3 rating at 400 V is 15 kW. For higher-voltage 690 V systems, the contactor is rated at 10 kW. These ratings govern the switching of squirrel-cage motors during starting and running; the contactor is designed for the high inrush and inductive load of that duty class. The auxiliary contact block handles 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V — enough for signalling and control circuits in most panels. The operating range is 0.8 to 1.1 times rated voltage at both 50 Hz and 60 Hz, so coil pick-up and hold are reliable across typical line variations. Mechanical life is rated at 10 million operations typical, with maximum switching rates of 1200 cycles/hour at AC-1, 1000 at AC-3, and 250 at AC-4.
Integration: panel fit and wiring
Side-by-side mounting is permitted, so multiple contactors can be ganged without spacing gaps — useful when building a motor starter cluster in a compact panel. Main circuit terminals accept stranded wire up to 2x 25 mm²; the control circuit accepts 2x (0.5 to 1.5 mm²) solid or 2x (0.75 to 2.5 mm²) stranded. Wire preparation is straightforward for panel builders: strip lengths are standard for screw terminals, and the spring-cage auxiliary terminals (if fitted) take ferruled conductors.