SIRIUS S2 frame for motor and resistive loads
The 3RT2035-3AH00 is a SIRIUS S2 power contactor — the middle frame in Siemens' S0/S2/S3 lineup, sized for motor switching up to 40 A at 480 V in AC-3 duty. That 40 A at 480 V rating means it handles a 25 hp motor at 480 V without a separate overload relay derating the contactor itself.
DIN rail fit and panel clearance
Width is 55 mm — that's three standard 18 mm module spaces on the DIN rail, so it occupies the same footprint as a 3-pole MCB or a small soft starter. Height is 114 mm. That side clearance is half the usual — you can pack contactors side-by-side with just a 6 mm gap between them, saving rail space in a dense panel.
Switching frequency and duty cycle limits
Maximum switching rate varies by duty class: 1,200 operations/hour in AC-1 (resistive), 1,000 ops/h in AC-3 (motor start/run), and 300 ops/h in AC-4 (plugging/inching). For a conveyor running at 20 starts per hour, the AC-3 limit is irrelevant — but for a rapid-reversing hoist or a weld-gun controller, the AC-4 ceiling of 300 ops/h (one cycle every 12 seconds) is the hard constraint. Arcing time is 10–20 ms, and the AC operating time is 10–18 ms. That means total break time is under 40 ms from coil dropout to arc extinction — fast enough for most safety circuits, but not a semiconductor-grade speed for a zero-crossing application.
Temperature envelope and storage
Operating ambient is -25 to +60 °C — standard for a panel-mounted contactor.