The Siemens 3RT1034-3AH00 is a SIRIUS power contactor in the S2 frame size, rated for motor switching up to 18.5 kW at 500 V and 10 kW at 690 V. The IP20 front protection means the contactor is safe for touch during operation inside an enclosure, while the screw-type terminals on the main circuit accept solid conductors up to 2x 2.5 mm² and stranded up to 2x 25 mm².
Switching performance and thermal limits
The contactor handles AC-3 duty at 400 V with a 15 kW rating, and AC-4 at 400 V at 29 A — the AC-4 figure governs reversing or inching applications where the contacts break full motor current. Maximum operating frequency varies by duty: 1 200 cycles/hour for AC-1 resistive loads, 1 000 for AC-3, and 250 for the heavy AC-4 regime. The coil operates at 50 Hz with a voltage tolerance of 0.8 to 1.1 times rated, and arcing time sits between 10 and 15 ms.
The contactor occupies 55 mm width, 112 mm height, and 115 mm depth — check gland plate clearance for that depth when the panel door closes. Solid conductors: 2x 0.25 to 2.5 mm² for control circuits; stranded: 2x 0.75 to 25 mm² for power wiring. The main circuit terminals are screw-type, rated for a minimum 16 mm² conductor at 40 °C.