SIRIUS Size S2 power contactor, 65 A at 480 V — spring terminals, no auxiliaries
The Siemens 3RT2037-3AP06 is a SIRIUS Size S2 power contactor rated for 65 A at 480 V in AC-3 duty — the motor-switching curve that governs most conveyor, pump, and fan loads. The 230 V 50 Hz coil pulls in reliably across the operating range, and spring-type terminals on both main and coil circuits eliminate the torque check needed on screw-clamp parts. No auxiliary switch block is fitted (: 18...1 means the main contact count is 3 NO + 1 NC, with no aux deck), so if your BOM calls for mirror contacts or early-make signals, plan a separate auxiliary contactor or a side-mount block. The contactor mounts via screw or snap-on onto 35 mm DIN rail per EN 60715. Clearance requirements are modest: 10 mm upward, 10 mm forward, 10 mm downward, and 6 mm at the side. The mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward, which helps when fitting into a crowded gland-plate area or a swing-frame subpanel.
Switching frequency and contact ratings — what the numbers mean for your cycle profile
Maximum switching rates are duty-dependent: 800 cycles/hour in AC-1 (resistive), 700/h in AC-3 and AC-3e (standard motor start/run), 400/h in AC-2 (slip-ring motor), and 200/h in AC-4 (plugging/inching) (–,). For a conveyor running 30-second cycles, the AC-3 limit of 700/h translates to roughly one start every 5 seconds — generous headroom. But if your application includes reversing or jogging (AC-4), the 200/h ceiling means a 15-second minimum interval between operations; exceeding that accelerates contact wear. The auxiliary contact ratings (–) cover the common control voltages: 6 A at 24 V, 2 A at 48/60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, 3 A at 400 V, 0.6 A at 440 V, and 2 A at 500 V. The 10 hp rating at 230 V gives a quick motor-size reference for North American panels. Arcing time runs 10–20 ms; operate time is 10–18 ms.
Environmental limits and wiring
Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C. The spring terminals accept 2x 0.5–2.5 mm² solid or stranded wire. Mechanical life is rated at 10 million operations typical.