SIRIUS S2 Power Contactor — 3RT1034-1AL20
The Siemens 3RT1034-1AL20 is a SIRIUS power contactor in the S2 frame size, designed for switching motor loads in industrial control panels. It mounts on 35 mm DIN rail per DIN EN 50022 via screw and snap-on fastening, with a 55 mm width that fits standard panel layouts. Rated for AC-2 duty at 15 kW on a 400 V supply, this contactor handles wound-rotor motor applications where moderate inrush and frequent switching are expected. At 500 V it delivers 18.5 kW, and at 690 V it provides 10 kW — covering the common European motor voltage tiers.
Duty Cycle and Switching Frequency
Maximum switching frequency varies by duty class: 1,200 operations per hour at AC-1 (resistive loads), 1,000 at AC-3 (squirrel-cage motors), 750 at AC-2, and 250 at AC-4 (plugging/inching). The AC-4 limit reflects the heavier arc stress during reversing or jogging cycles.
Termination and Wiring
Main current circuit uses screw-type terminals. Solid wire capacity ranges from 2x (0.5 to 1.5 mm²) up to 2x (0.75 to 4 mm²), while stranded accepts 2x (0.75 to 25 mm²) — enough for the full rated current without paralleling. Auxiliary contact wiring uses the smaller solid range.
Environmental and Protection Ratings
Operating temperature range is -25 to +60 °C, with storage from -55 to +80 °C. Pollution degree 3 suits it for control panels in industrial environments with conductive contamination. The enclosure is IP20 on the front (finger-safe terminals) and IP00 at the terminal points — install inside a cabinet or enclosure.