The Siemens SIMATIC 3RK1304-5KS40-2AA0 is a direct motor starter in the SIMATIC motor starter family, designed for starting and protecting three-phase induction motors in industrial automation lines. Rated for 24 V DC control supply (20.4 to 28.8 V operating range) and switching up to 2 A at 400 V AC, with a short-circuit breaking capacity of 100 kA at 400 V. The enclosure is rated IP65, so the unit is dust-tight and protected against low-pressure water jets — suitable for washdown environments or outdoor cabinets where hose-down cleaning is routine. Mounting is by screw fixing, and the unit can be installed vertically or horizontally.
Because it is active and widely specified, availability is generally good through independent distribution. There is no need to hunt for surplus or alternative cross-references on this code.
Integration and I/O
The starter includes 4 digital inputs (M12 socket) and 2 bytes of input and output data on the PROFINET or PROFIBUS DP fieldbus. That means it can report motor status (running, fault, overload) and accept start/stop commands directly over the network without a separate remote I/O module. The PROFINET and PROFIBUS DP protocols are both supported, so it fits into either Siemens S7 or third-party controller environments. Power dissipation is 3.888 W both with and without the bypass circuit active, so the thermal load on the cabinet is consistent regardless of operating state. The unit also has a vibration resistance of 2g and shock resistance of 15g / 11 ms, which is typical for industrial machine-mounted gear.