The Siemens 3RT1034-1AN64 is a SIRIUS power contactor in size S2, rated for motor switching at 15 kW in AC-2 duty at 400 V and 18.5 kW at 500 V.
AC-3 at 400 V is the standard squirrel-cage motor duty; the part carries that at 1000 operations per hour max. AC-1 resistive load maxes at 1200 1/h.
Terminal and wiring reality
Screw-type terminals on the main circuit accept solid conductors up to 2x 4 mm² (max 2x 0.75–4 mm²) and stranded up to 2x 25 mm². That covers most motor feeds up to 18.5 kW without needing lug adapters.
