What it is and what it does
The Siemens 3RT2036-1AL20-ZW97 is a SIRIUS power contactor, size S2, designed for switching motor loads and resistive loads in industrial control panels. It carries a rated current of 52 A at 480 V, which covers common 480 V three-phase motor circuits up to that load — think conveyors, pumps, or compressors on a 480 V line. The contactor includes an auxiliary switch, giving you a spare N/O or N/C contact for feedback to a PLC or to seal in the coil circuit without adding a separate block. Mounts via screw or snap-on onto a 35 mm DIN rail per DIN EN 60715, and the mounting position is flexible: ±180° rotation on a vertical surface, plus ±22.5° tilt forward/backward — useful when you're squeezing it into a tight enclosure corner.
Key ratings and what they mean for fit
The 52 A at 480 V rating is the AC-1 resistive load current — that's the maximum continuous current the main contacts can carry in a resistive circuit. For motor loads (AC-3 duty), the contactor is rated lower, but the 52 A figure tells you the contactor's thermal capacity: it can handle the inrush of a motor up to about 25 hp at 480 V without welding the contacts. The coil terminals are screw-type, so you'll need a screwdriver for termination — no spring-cage here. The main power terminals accept 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid or stranded wire. Dimensions: 114 mm high, 55 mm wide, 130 mm deep. The 55 mm width is the standard S2 footprint.