SIRIUS S2 power contactor — 3RT1034-1BG44
The Siemens 3RT1034-1BG44 is a SIRIUS S2 power contactor, screw-type terminals on the main current circuit, rated for motor switching across common industrial voltages. It mounts via screw and snap-on onto 35 mm DIN rail per EN 50022, with side-by-side mounting permitted — no derating gaps required between units in a row.
Ratings and what they mean for fit
At 400 V AC, the contactor is rated 18.5 kW for AC-3 duty (squirrel-cage motor starting) and 15 kW for AC-2 duty (slip-ring motor starting) — the AC-3 figure is the one to size against for standard induction motors. At 690 V AC, the AC-3 rating drops to 10 kW, reflecting the higher voltage stress on the switching gap. For DC switching, it handles 10 A at 24 V, 2 A at 60 V, 1 A at 110 V, and 0.3 A at 220 V — the DC arc is harder to extinguish, so these are lower than the AC numbers. The AC-4 rating at 400 V is 29 A — that's for inching or plugging duty where the contactor makes and breaks stalled-rotor current; mechanical life is 10 million operations typical. Maximum operating frequency varies by duty: 1200 ops/h for AC-1 (resistive), 1000 ops/h for AC-3, 750 ops/h for AC-2, and 250 ops/h for AC-4 — the AC-4 limit is the binding constraint for high-cycle jogging applications.
Terminal capacity and wiring
Screw terminals accept solid wire: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), max 2x (0.75 to 4 mm²). Stranded: 2x (0.75 to 25 mm²). Solid or stranded: 2x (0.75 to 16 mm²). Minimum permissible conductor cross-section at 40 °C is 16 mm² — relevant when sizing for continuous full-load current in a warm cabinet.
Environmental and compliance
Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C. Pollution degree 3 — suitable for industrial environments with conductive dust or humidity. IP20 on the front (finger-safe), IP00 at the terminals — the terminal area must be inside an enclosure. RoHS compliance date is May 1, 2012. Arcing time is 10 to 15 ms; DC operating time is 20 to 30 ms. Pickup factor is 0.8 (80% of rated coil voltage), dropout factor is 1.1 (110% of rated voltage before release).
Sourcing and procurement
This is an active-production part, sourced through independent distribution channels. Availability and current pricing are confirmed at quote time against an RFQ.