The Siemens 3RT2035-1AC10 is a SIRIUS power contactor in Size S2, rated 40 A at 480 V. That 480 V figure is the AC-3 motor-switching rating — the one that decides whether it holds a 40 A motor load under full locked-rotor inrush. It also carries a 1 200 ops/h maximum at AC-1 (resistive load) and 1 000 ops/h at AC-3, so it keeps up with a fast-cycling conveyor or pump station without derating the duty cycle. Mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 60715. The mounting position is flexible — +/-180° rotation on a vertical surface, plus +/-22.5° tilt forward/backward — so it fits into tight enclosures or angled subpanels without a special bracket.
Integration & Panel Fit
Dimensions: 114 mm high, 55 mm wide, 130 mm deep. The 55 mm width is a standard Size S2 footprint — it occupies one 55 mm slot on the DIN rail, leaving room alongside for overload relays or bus bars. Clearances: 10 mm upwards, 10 mm forwards, 10 mm downwards, 6 mm at the sides. That 6 mm side gap is tighter than the vertical ones; plan for it when grouping contactors side-by-side. Operating temperature range -25 to +60 °C; storage range -55 to +80 °C. The storage limit governs handling during shipping or off-season storage — the contactor can sit in a cold warehouse but must be at operating temp before energizing the coil. Coil connection uses screw-type terminals. Main contact wiring accepts 2x (0.5... 1.5 mm²) solid or stranded, or 2x (0.75... 2.5 mm²). That's a standard range for control panels — no need for special ferrules or oversized lugs.
Duty & Mechanical Life
Mechanical life is 10 000 000 operations typical — that's the contactor body itself, not the contacts under load. Switching rates: AC-1 max 1 200 ops/h, AC-2 max 750 ops/h, AC-3 max 1 000 ops/h, AC-4 max 300 ops/h. The AC-4 rate (300 ops/h) is the limiting factor for plugging or inching duty — if the application reverses the motor frequently, stay under that ceiling. Auxiliary switch is included as standard — no separate add-on block needed for basic signaling or interlocking. Arcing time is 10... 20 ms; the coil dropout time at AC is 10... 18 ms. That dropout window matters for sequencing: if you're interlocking two contactors, the break-before-make gap is at least 10 ms.