Siemens SIRIUS 3RT2035-3XJ84-0LA2 — what it is
Mounting is via screw or snap-on onto a 35 mm standard mounting rail per DIN EN 60715, giving you the option to clip it onto a DIN rail or bolt it directly to a backplate. The mounting position allows +/-180° rotation on a vertical surface and +/-22.5° tilt forward/backward, which helps when routing cables in a dense panel. The coil connection uses spring-type terminals, so you strip the wire, push it in — no screwdriver needed for the magnet coil circuit. The main contact terminals are rated IP00 (no finger-safe protection on the power side), while the front face carries IP20, meaning the operator interface is touch-safe once installed.
Key ratings and what they mean for fit
The headline switching ratings are 40 A at 480 V and 41 A at 600 V. Those are the AC-3 duty currents — the values that govern motor switching. If your motor FLA at 480 V is under 40 A, this contactor has headroom. At 600 V, the 41 A rating is slightly higher, reflecting the fact that motor current drops as voltage rises for the same horsepower. For DC switching, the contactor is rated 6 A at 24 V DC, 2 A at 48 V DC, and 1 A at 110 V DC. These are DC-1 resistive load values — inductive DC loads (like DC motor brakes or solenoids) will need derating. The arcing time is 10 to 20 ms, which is typical for a DC-interrupting contactor of this size. The contactor is rated for continuous operation from -40 °C to +70 °C ambient, with storage from -55 °C to +80 °C. That covers most indoor panel environments, including unheated warehouses. Maximum operating altitude is 2 000 m — above that, you need to derate for air density. Mechanical endurance is 10 million operating cycles typical.
Physical fit — dimensions and spacing
The contactor measures 55 mm wide, 114 mm high, and 178 mm deep. The depth includes the coil terminals and arc chutes — verify clearance to the enclosure door or cover panel. Side spacing to adjacent devices is 6 mm minimum; vertical spacing (upwards, downwards, forwards) is 10 mm. These are the free-air clearance requirements for heat dissipation and arc containment. The S2 frame size is the mechanical platform. If you are replacing a different S2 contactor from the same SIRIUS family, the footprint and mounting hole pattern are identical — the 3RT2035-3XJ84-0LA2 drops into the same DIN rail or screw-mount position.