What it is and what it does
The Siemens 3RT2037-3AV00 is a SIRIUS power contactor in size S2, rated for switching motor loads up to 65 A at 480 V in AC-3 duty — that's the current it can make and break under full-load motor starting conditions, not just resistive heating. Spring-type terminals on the magnet coil and main contacts accept 2x (0.5... 2.5 mm²) solid or stranded wire, so no screw torque checks on the line. Mounting is screw and snap-on onto 35 mm standard mounting rail per DIN EN 60715, with a +/-180° rotation possible on a vertical surface and tilt of +/-22.5° forward/backward — useful when the panel layout forces an odd orientation. The contactor's footprint is 55 mm wide, 114 mm tall, and 130 mm deep, so it fits a standard S2 slot in a motor control center or standalone enclosure.
Clearances and switching performance
Clearance requirements are tight: 10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm at the side — so it packs into a dense panel without needing extra breathing room between contactors. Arcing time runs 10 to 20 ms, and the mechanical life is typical 10 million operations, which for a conveyor zone that cycles once every 10 seconds translates to over three years of continuous service before the contacts wear.