What this part is and what it does
The Siemens 3RT1023-1AM70-0KR0-ZW97 is a 3-pole power contactor from the SIRIUS 3RT1 series, rated for AC-3 duty at 9 A and 4 kW at 400 V. The coil is wound for 200-240 V AC. This is a Size S0 unit with screw terminals, designed for switching motor loads in control panels — think pumps, fans, and small conveyors on a DIN-rail assembly.
What the AC-3 rating means for fit
The AC-3 rating of 9 A and 4 kW at 400 V defines the contactor's capability for starting and stopping squirrel-cage motors under full load — the standard duty for a general-purpose motor contactor. The 200-240 V AC coil means the control circuit must supply that voltage range; a 24 V DC coil variant would be a different order code. The Size S0 footprint is the standard 45 mm width for this class, fitting a common DIN-rail slot.