The Siemens 3RK1323-5BS44-3AA3 is a reversing starter — a compact motor-starting assembly that handles forward/reverse control in a single enclosure.
The AC-3 rating of 3 A at 400 V governs the motor size this starter can handle — typically a 1.1 kW to 1.5 kW three-phase motor depending on the duty cycle. Four digital inputs are available via two M12 sockets, parameterizable for different sensor types. There are no digital outputs on this variant. The solid-state motor protection eliminates the need for a separate overload relay, and brake control for 400 V AC is built in — no external brake rectifier needed for that voltage. Communication and power are both carried through AS-i shaped cables using the cutting/clamping method, which simplifies daisy-chaining along the line. The operating voltage range is 400 to 500 V AC, and the control supply is 24 V DC (20.4 to 28.8 V).
Dimensions are 91 mm deep, 130 mm wide, and 250 mm high. The front addressing socket allows parameterization without opening the enclosure. The main energy infeed and load-side outgoing feeder both use sockets according to ISO 23570, which standardizes the connector interface across the AS-i product family.