The Siemens 3RT2035-3NE34 is a SIRIUS power contactor in Size S2, built for switching motor loads and resistive loads in industrial control panels. It's a current-production part, still in active manufacture. Coil acceptance spans 48 to 80 V, covering both AC and DC supplies — no separate coil variant needed if your control voltage sits in that band. The magnet coil terminates on spring-type terminals, so you're not cranking down screws on the coil leads. Mounting is straightforward: screw it down or snap it onto standard 35 mm DIN rail per DIN EN 60715. The contactor can be rotated ±180° on a vertical surface and tilted ±22.5° forward or backward, giving you some play in tight enclosures.
Mounting and clearances
The 3RT2035-3NE34 measures 114 mm high, 55 mm wide, and 178 mm deep — that depth includes the coil terminals and arc chamber. Side clearance to adjacent devices is 6 mm; forward, upward, and downward gaps all need 10 mm. Keep those numbers in mind when laying out a crowded DIN rail.
Switching duty and operating rates
Operating rates vary by duty: AC-1 (resistive) allows up to 1,200 operations per hour; AC-3 (motor starting) rates 1,000 ops/h; AC-4 (plugging/inching) drops to 300 ops/h. The arcing time runs 10-20 ms, and the contactor's mechanical life is rated at 10 million operations typical. Coil inrush peaks at 1 A, then settles to a 2 VA holding draw at 50 or 60 Hz. Pick your control transformer accordingly — a small 24 V supply won't like that inrush if you're switching several contactors at once.